Definitions of the Trigonometric Functionsof an Acute Angle
BEFORE DEFINING THE TRIGONOMETRIC FUNCTIONS, we must see how to relate the angles and sides of a right triangle.
A right triangle is composed of a , the angle at C, and two acute angles, which are angles less than a right angle.& It is conventional to label the acute angles with Greek letters. We will label the angle at B with the letter & ("THAY-ta"). &And we will label the angle at A with the letter & ("fie").
As for the sides, the side AB, opposite the right angle, is called the hypotenuse ("hy-POT'n-yoos"). &Each acute angle is formed by the hypotenuse and the side adjacent to the angle. &Thus, angle & is formed by the hypotenuse and side BC. &Angle & is formed by the hypotenuse and side
With respect to angle &, though, side AC is its opposite side. &While side BC is the side opposite &.
The ratios of
Any two sides of the triangle will have a
-- a relationship -- to one another.
&It&is possible to form six such ratios: &the ratio of the opposite si the adjacent si and so on. Those six ratios have historical names and abbreviations, with which the student will have to make peace. &They are the following.
sine of &&
&&opposite&&hypotenuse
cosecant of &&
hypotenuse&&opposite
cosine of &&
&&adjacent&&hypotenuse
secant of &&
hypotenuse&&adjacent
tangent of &&
opposite&adjacent
cotangent of &&
&adjacentopposite
Notice that each ratio in the right-hand column is the inverse, or the reciprocal, of the ratio in the left-hand column.
The reciprocal of sin & is csc & ; and vice-versa.
The reciprocal of cos & is sec &.
And the reciprocal of tan & is cot &.
Each ratio moreover is a function of the acute angle. &That is, one quantity is a "function" of another if its value depends on the value of the other. &The circumference of a circle
is a function of the radius, because the size of the circumference depends on the size of the radius, and when the radius changes, the circumference also will change. &As we will see in the next , the value of each ratio depends only on the value of the acute angle.
That is why we say that those ratios are functions of the acute angle. &We call them the trigonometric functions of an acute angle. &All of trigonometry is based on the
of those functions.
Problem 1.&&&Complete the following with either "opposite," &"adjacent to," or "hypotenuse."
To see the answer, pass your mouse over the colored area. To cover the answer again, click "Refresh" ("Reload").
a) In a right triangle, the side opposite the right angle is called the
hypotenuse.
b) CA is called the side
opposite angle &.
c) BC is called the side
adjacent to angle &.
d) AC is called the side
adjacent to angle &.
e) BC is called the side
opposite angle &.
Problem 2.&&&The sides of a right triangle are in the ratio 3 : 4 : 5, as shown.
&Name and evaluate the six trigonometric functions of angle &.
Problem 3.&&& The sides of a right triangle are in the ratio 8 : 15 : 17, as shown. &Name and evaluate the six trigonometric functions of angle &.
Notice that the sides of this triangle satisfy, as they must, the :
Problem 4.&&&A straight line makes an angle & with the x-axis. &The value
of which function of & is equal to its ?
Problem 5. &The
of a triangle.&&&Every triangle, right-angled or not, will have at least two acute angles.
Let them be the base angles at A and B, so that the base will be the side c. &Show that the height h drawn to that base is
_____c_____cot A + cot B
Hint: &The height h will cut the entire triangle into two right triangles.
Let x be the segment of the base containing the angle A. &Then the remaining segment is the difference between the whole c and that segment: &c&&&x.
In the right triangle containing the acute angle A,
cot A, & or & x = h cot A . & . & . &(1)
In the right triangle containing the acute angle B,
cot B, & or & c & x = h cot B.
On substituting the expression for x from line (1),
c & h cot A = h cot B,
which implies
c = h cot A + h cot B = h(cot A + cot B).
Therefore, on solving for h,
_____c_____cot A + cot B
Problem 6. &The area of a triangle.&&Prove: &The area of a triangle is equal to one-half the sine of any angle
times the product of the two sides that make the angle.
Specifically, prove that
Area of triangle ABC = ½ sin A bc = ½ bc sin A.
The area of a triangle is equal to one-half the base times the . &In triangle ABC, let the base be c. &Then
Area = ½ ch.
sin A = h/b,
h = b sin A.
Therefore in the expression for the Area, replace h with b sin A:
Area = ½ cb sin A.
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E-mail: &themathpage@Learn the Pythagorean Theorem. The Pythagorean Theorem describes the relationship between the sides of a right triangle. It states that for any right triangle with sides of length a and b, and hypotenuse of length c, a2 + b2 = c2.
Make sure that your triangle is a right triangle. The Pythagorean Theorem only works on right triangles, and by definition only right triangles can have a hypotenuse. If your triangle contains one angle that is exactly 90 degrees, it is a right triangle and you can proceed.
Right angles are often notated in textbooks and on tests with a small square in the corner of the angle. This special mark means "90 degrees."
Assign variables a, b, and c to the sides of your triangle. The variable "c" will always be assigned to the hypotenuse, or longest side. Choose one of the other sides to be a, and call the other side b (it doesn't m the math will turn out the same). Then copy the lengths of a and b into the formula, according to the following example:
If your triangle has sides of 3 and 4, and you have assigned letters to those sides such that a = 3 and b = 4, then you should write your equation out as: 32 + 42 = c2.
Find the squares of a and b. To find the square of a number, you simply multiply the number by itself, so a2 = a x a. Find the squares of both a and b, and write them into your formula.
If a = 3, a2 = 3 x 3, or 9. If b = 4, then b2 = 4 x 4, or 16.
When you plug those values into your equation, it should now look like this: 9 + 16 = c2.
Add together the values of a2 and b2. Enter this into your equation, and this will give you the value for c2. There is only one step left to go, and you will have that hypotenuse solved!
In our example, 9 + 16 = 25, so you should write down 25 = c2.
Find the square root of c2. Use the square root function on your calculator (or your memory of the multiplication table) to find the square root of c2. The answer is the length of your hypotenuse!
In our example, c2 = 25. The square root of 25 is 5 (5 x 5 = 25, so Sqrt(25) = 5). That means c = 5, the length of our hypotenuse!
Learn to recognize Pythagorean Triple Triangles. The side lengths of a Pythagorean triple are integers that fit the Pythagorean Theorem. These special triangles appear frequently in geometry text books and on standardized tests like the SAT and the GRE. If you memorize the first 2 Pythagorean triples, in particular, you can save yourself a lot of time on these tests because you can immediately know the hypotenuse of one of these triangles just by looking at the side lengths!
The first Pythagorean triple is 3-4-5 (32 + 42 = 52, 9 + 16 = 25). When you see a right triangle with legs of length 3 and 4, you can instantly be certain that the hypotenuse will be 5 without having to do any calculations.
The ratio of a Pythagorean triple holds true even when the sides are multiplied by another number. For example a right triangle with legs of length 6 and 8 will have a hypotenuse of 10 (62 + 82 = 102, 36 + 64 = 100). The same holds true for 9-12-15, and even 1.5-2-2.5. Try the math and see for yourself!
The second Pythagorean triple that commonly appears on tests is 5-12-13 (52 + 122 = 132, 25 + 144 = 169). Also be on the lookout for multiples like 10-24-26 and 2.5-6-6.5.
Memorize the side ratios of a 45-45-90 right triangle. A 45-45-90 right triangle has angles of 45, 45, and 90 degrees, and is also called an Isosceles Right Triangle. It occurs frequently on standardized tests, and is a very easy triangle to solve. The ratio between the sides of this triangle is 1:1:Sqrt(2), which means that the length of the legs are equal, and the length of the hypotenuse is simply the leg length multiplied by the square root of two.
To calculate the hypotenuse of this triangle based on the length of one of the legs, simply multiply the leg length by Sqrt(2).
Knowing this ratio comes in especially handy when your test or homework question gives you the side lengths in terms of variables instead of integers.
Learn the side ratios of a 30-60-90 right triangle. This triangle has angle measurements of 30, 60, and 90 degrees, and occurs when you cut an equilateral triangle in half. The sides of the 30-60-90 right triangle always maintain the ratio 1:Sqrt(3):2, or x:Sqrt(3)x:2x. If you are given the length of one leg of 30-60-90 right triangle and are asked to find the hypotenuse, it is very easy to do:
If you are given the length of the shortest leg (opposite the 30-degree angle,) simply multiply the leg length by 2 to find the length of the hypotenuse. For instance, if the length of the shortest leg is 4, you know that the hypotenuse length must be 8.
If you are given the length of the longer leg (opposite the 60-degree angle,) multiply that length by 2/Sqrt(3) to find the length of the hypotenuse. For instance, if the length of the longer leg is 4, you know that the hypotenuse length must be 4.62.
Understand what "Sine" means. The terms "sine," "cosine," and "tangent" all refer to various ratios between the angles and/or sides of a right triangle. In a right triangle, the sine of an angle is defined as the length of the side opposite the angle divided by the hypotenuse of the triangle. The abbreviation for sine found in equations and on calculators is sin.
Learn to calculate sine. Even a basic scientific calculator will have a sine function. Look for a key marked sin. To find the sine of angle, you will usually press the sin key and then enter the angle measurement in degrees. On some calculators, however, you must enter the degree measurement first and then the sin key. You will have to experiment with your calculator or check the manual to find out which it is.
To find the sine of an 80 degree angle, you will either need to key in sin 80 followed by the equal sign or enter key, or 80 sin. (The answer is -0.9939.)
You can also type in "sine calculator" into a web search, and find a number of easy-to-use calculators that will remove any guesswork.
Learn the Law of Sines. The Law of Sines is a useful tool for solving triangles. In particular, it can help you find the hypotenuse of a right triangle if you know the length of one side, and the measure of one other angle in addition to the right angle. For any triangle with sides a, b, and c, and angles A, B, and C, the Law of Sines states that a / sin A = b / sin B = c / sin C.
The Law of Sines can actually be used to solve any triangle, but only a right triangle will have a hypotenuse.
Assign the variables a, b, and c to the sides of your triangle. The hypotenuse (longest side) must be "c". For the sake of simplicity, label the side with the known length as "a," and the other "b". Then assign variables A, B, and C to the angles of the triangle. The right angle opposite the hypotenuse will be "C". The angle opposite side "a" is angle "A," and the angle opposite side "b" is "B".
Calculate the measurement of the third angle. Because it is a right angle, you already know that C = 90 degrees, and you also know the measure of A or B. Since the internal degree measurement of a triangle must always equal 180 degrees, you can easily calculate the measurement of the third angle using the following formula: 180 – (90 + A) = B. You can also reverse the equation such that 180 – (90 + B) = A.
For example, if you know that A = 40 degrees, then B = 180 – (90 + 40). Simplify this to B = 180 – 130, and you can quickly determine that B = 50 degrees.
Examine your triangle. At this point, you should know the degree measurements of all three angles, and the length of side a. It is now time to plug this information into the Law of Sines equation to determine the lengths of the other two sides.
To continue our example, let's say that the length of side a = 10. Angle C = 90 degrees, angle A = 40 degrees, and angle B = 50 degrees.
Apply the Law of Sines to your triangle. We just need to plug our numbers in and solve the following equation to determine the length of hypotenuse c: length of side a / sin A = length of side c / sin C. This might still look a bit intimidating, but the sine of 90 degrees is a constant, and always equals 1! Our equation can thus be simplified to: a / sin A = c / 1, or just a / sin A = c.
Divide the length of side a by the sine of angle A to find the length of the hypotenuse! You can do this in two separate steps, by first calculating sin A and writing it down, and then dividing by a. Or you can key it all into the calculator at the same time. If you do, remember to include parentheses after the division sign. For example, key in either 10 / (sin 40) or 10 / (40 sin), depending on your calculator.
Using our example, we find that sin 40 = 0.. To find the value of c, we simply divide the length of a by this number, and learn that 10 / 0. = 15.6, the length of our hypotenuse!
How do I find the 3 angles of a triangle when only the 3 sides are given?
You would use the trigonometric functions (sine, cosine and tangent).
How do I find the area of a triangle if only the length of the hypotenuse is given?
wikiHow Contributor
To get the area of a triangle, you need the base and the height or the length of all three sides. Since the angles are unknown, it is impossible.
Can I find the hypotenuse if I only have the length of the two other sides?
Yes. Use the Pythagorean theorem.
How do I get the 2 sides of the right triangle if the hypotenuse and perimeter are given?
You don't have enough information to find the two sides.
How do I find the area of a right triangle whose base is 1.2m and hypotenuse is 3.7m?
Use the Pythagorean theorem to find the other side, which is also the height of the triangle. Half the base multiplied by the height is the area.
How do I calculate the hypotenuse if I have the base and it is a right triangle?
You will also have to know the height before you can find the hypotenuse.
Can I use slope to find the hypotenuse?
Yes, if you're prepared to apply trigonometry to the question.
If I know the hypotenuse and one side of a right triangle, how do I find the angle between them?
Find the cosine of the angle by dividing the side by the hypotenuse, then look up the angle on a trig table.
How can I find the length of the other lines when I only have the hypotenuse?
You can't.
How do I find the length of a hypotenuse?
Does the Pythagorean theorem apply when I know the hypotenuse and the base to fix the length of the rise in a right triangle?
How to calculate one side of a triangle if I know one side and the three angles?
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&&&&2014 新版八年级英语下册半期考试复习第一至第五单元知识点总结 unit 1 what’s the matter 一、基础知识 1. what’ s the matter 怎么啦出什么事情了 【解析】matter/ ' mt(r)) /n.问题；事情 what’ s the matter with you = what’s the trouble with&&&& you = what’ s wrong with you 你怎么了 【注】 ： matter 和 trouble 为名词， 其前可加 the 或形容词性物主代词，wrong 是 adj. 不能加 the 【用法】用于询问某人有什么病或某人遇到什么麻烦、问题其后跟询问对象时， 与介词 with 连用。 即： what’s the matter with sb. = what’s your trouble = what’s up = what happens to sb. — what’s the matter with you
— i have a bad cold. 2. i had a cold.我感冒了。 have a cold=catch a cold=have the flu 感冒 have a fever 发烧 have a cough 咳嗽 have a toothache 牙疼 have a headache 头疼have a stomachache 胃疼，肚子疼3. 身体部位+ache（疼痛）构成新的复合词 stomach+ache=stomachache 背痛 4. much too+ 形容词，意为 太...... ，too much+名词，意为 很多，大量 。 head+ache=headache tooth+ache=toothache back+ache=backache 后5. enough【形容、副词】足够的/地，enough 放在名前后，形副后。 good enough 足够好，enough money=much money 6. lie down 躺下， lie 躺，躺着，过去式 lay；lie 说谎，过去式 lied 7. maybe ―或许‖，常用于句首，表示可能性，后加句子。maybe you are right. may be，是情态动词+be 的结构，意为―可能，也许‖，后加名词、代词或形容词。he may be angry. 8. sound like+名词代词和从句：it sounds like you don’t know the truth. it sounds like a good idea. sound+形容词，―听起来，好像‖，the music sounds nice. 9. need 需要，实义动词 need+名词，需要某物； need to do sth.需要做某事，主语通常是人，表示人主动的动作：you need to listen carefully during class. need doing sth.主语通常是物，表示被动的动作：your dirty clothes need washing. 10. get off (the bus) 下（公交车） get on 上车 11. agree 同意，赞同； agree with sth. 同意某事 如：i agree with that idea. agree to sb. 同意某人的意见 如：i agree to lilei.112. trouble 问题， 麻烦 ；be in trouble 遇到麻烦，make trouble 制造麻烦 ，have trouble (in) doing sth. =have difficulties (in) doing sth 做......有麻烦。 13. right away=right now=at once，意为 马上 。 14.【复习】 advice [不可数名词]劝告，建议，向…征求意见， give sb. advice on sth.就某事给某人建议； advise [动词] advise sb. to do sth. 建议某人做某事 advise sb. doing sth. 15. 【复习】exercise 练习、锻炼 当 exercise 意为―练习‖时，为可数名词 即可加 s 当 exercise 意为―锻炼‖时，为不可数名词 即不加 s 16. hurt 及物动词，使……疼痛，……受伤，he hurt his leg while exercising. 不及物动词，……（部位）疼。 his leg hurt badly. 干净的 ，cleaner 意为 清洁17. clean 【动词】打扫，clean the classroom 打扫教室， 【形容词】 工 。18. hit （用手或器具）打；击打 the boy hit the dog with a stone. hit sb. on the head/ nose/ back 打某人的头、鼻子、后背，on 用在所打较硬的部位； hit sb. in the face/ eye/ stomach 打某人的脸、眼睛、肚子，in 用在所打较软的部位。 19. be used to sth./ doing sth.习惯于、适应了……、做某事，强调状态； his grandpa was used to country life. mary is not used to getting up early in the morning. get/ become used to sth./ doing sth. ―变得习惯，逐渐适应……‖强调过程、动作： it’s difficult for one to get used to another country’s habit. 20. 【复习】free [形容词]空闲的 free time；免费的 the drink is for free；自由的 i want to become a free bird. free【动词】使……解脱，得到自由：he could not free his arm. 21. run out 用完，用尽 when his water run out, he knew that he would have to do something to save his own life. 物 sth. run out. 某物用尽了。 人 sb. run out of sth. 人用尽了某物。he run out of all his money last night. 22. risk (sb.) to do sth. 冒险去做某事 take a risk=take risks 冒险 23. the importance of (doing) sth.（做）某事的重要性 we students should know the importance of (learning) english. importance n. 重要（性） ， important adj.重要的，unimportant adj.不重要的 做决定 ;24. decision 【名词】决定；抉择； make a decision make a decision to do sth.= decide to do sth. 。25. be in the control of …掌管，管理 the headmaster is in the control of this new school. be out of control 无法控制，无法管理 be under control 被控制住，在控制之中226. 【复习】mind 意为 介意，mind doing sth.介意做某事,would you mind my opening the window 27. give up (doing) sth. 放弃（做）某事，give up (playing) computer games； give up 后可接名词、代词和动词 ing 形式，也可不接，如: never give up easily. 二、重点语法 【反身代词】英语中共有八个反身代词，在使用时应注意和它所指的相应的对象在人称、性别、数上保 持一致。 数 人称 单数 复数 第一人称 myself ourselves 第二人称 yourself yourselves 第三人称 himself herself themselves itself【用法】 1. 可用作宾语，指的是宾语和主语表示同一个或同一些的人或事物。 如：maria bought herself a scarf. 2. we must look after ourselves very well.可用作表语，指的是表语和主语表示同一个或同一些人或事物。 如： she isn’t quite herself today.3.可用作主语或宾语的同位语，常用来加强语气。 i met the writer himself last week.如：she herself will fly to london tomorrow. 4. 用在某些固定短语当中。如： look after oneself / take care of oneself 照顾自己 teach oneself sth./ learn sth. by oneself 自学 enjoy oneself 玩得高兴，过得愉快 help oneself to sth 请自用……（随便吃/喝些……）. hurt oneself 摔伤自己 say to oneself 自言自语 leave sb. by oneself 把某人单独留下 buy oneself sth.给自己买……东西 introduce oneself 介绍……自己 【提醒】 1. 反身代词不能单独做主语，但可以做主语的同位语，起强调作用。 如：我自己能完成作业。 (正) i myself can finish my homework. / i can finish my homework（误）myself can finish my homework. myself. 2.反身代词表示―某人自己‖不能表示―某人的东西‖，因为它没有所有格的形式。表达―某人自己的（东西）‖时，须要用 one’s own.3如：我用我自己的蜡笔画画。 （误）i’m drawing with myself crayons. crayons.(正) i’m drawing with my ownunit 2 i’ll help to clean up the city parks 一、基本知识点 1. sick 生病的，有病的；可在句中作表语 mary could not come because she is sick. 也可作定语 a sick child 【区别 ill】ill 与 sick 同义；但是只在句中做表语，不做定语。mary could not come because she is ill. 2. cheer (sb.) up（让某人）变得高兴；振奋起来 the good news cheered up everyone in our class. 3. give out 分发；散发，相当于 hand out，the teacher is giving out/ handing out the test papers. give sth. out to sb. 意为 把某物分发给某人 。 4. volunteer 【名词】志愿者 【动词】义务做，自愿做（某事）volunteer to do sth. 自愿做某事 ， the girls could volunteer in an after-school study program. 5. used to do sth.过去/曾经(常)做某事，表示过去的习惯、动作或状态，并强调现在已经不再存在或发生。 there used to be a cinema here. 这里曾有一个照相机。 they told me stories about the past and how things used to be. 他们告诉我关于这里过去的故事。 6. alone 【形容词】独自一人的，无感情色彩：the musician enjoyed living alone and writing songs himself. lonely （感到）孤独寂寞的，带有很强的感情色彩，可做表语或定语。the lonely boy is not lonely now. 7. care for sb./sth.照顾；照料…… care 【名词】小心，关心 take care of=look after →【动词】care about sb./sth.关心，在意某人/事 →【形容词】careful 仔细的 / careless 粗心的 →【副词】carefully 仔细地 8. such ―这样的，这种，如此‖，用于修饰名词 such+ a/ an+形容词+单数名词：such a good day 多么美好的一天 /such an exciting match 多么 精彩的比赛 such+形容词+复数名词/不可数名词：such important decisions 多么重要的建议 such delicious food 多么美味的食物 如果名词前被 many, much, few, little 修饰时， 只能用 so， 而不用 such： so many sick children/ so little time 9. try out for…参加…选拔，争取成为…thirty football players tried out for the best player of the year. try out 试用，试验 10. journey 【名词】 （尤指长途）旅行，行程；trip【名词】多指短途旅行； travel【名词、动词】travel around the world →【名词】traveler 旅行者 11.【复习】be busy with sth. 12.【复习】try doing sth. 某人最大的努力去做某事 13.【复习】be worried about sb./ sth. = worry about sb./ sth. 担心某人、某事 14. raise money 集资，筹钱；raise money for…为……筹钱 raise【动词】举起；提高；募集 15. keep【动词】keep+名词，保留（某物） ；keep+形容词，保持 16.【形容词】broken 破损的，出毛病的；blind 瞎的，失明的；deaf 聋的；disabled 有残疾的，丧失能力 的；在句中做定语和表语。 17. make it possible (for sb.) to do sth.使（某人）做某事成为可能， you helped to make it possible for me to have lucky. make it +形容词(+for sb.) to do sth. 使（某人）做某事成为…；4忙于（做）什么事情 be busy doing sth. 尽力去做某事忙于（做）什么事情 try one’s best (to do sth.) 尽试着去做某事 try to do sth.think/find it +形容词 to do sth. 18. make a difference to…对……有影响；对……有作用，difference 前可以用 no, any, some, much 等修饰， 如 the rain made no difference to the game. hard-working makes much difference to study. 19. difficulty【可数/不可数】表示抽象意义的―困难‖时为不可数；表示具体的―难题、难事‖时为可数； have difficulty (in) doing sth.= have trouble (in) doing sth. 做某事有困难 20. train【动词】训练，trained 为过去分词，可做定语，意为―受过训练的‖a trained dog 21. be excited about sth. 对某事感到兴奋 ，everyone is excited about the good news. 【复习】excited 意为 兴奋的，修饰人；exciting 意为 令人兴奋/激动的，修饰物。 22. order【名词】命令，指示；顺序，次序【动词】订购；点（菜）follow the order。 23. change【动词】变化，改变 it’s hard for a person to change his life(style). 【名词】变化；零钱 change a for b 用 a 换成 b：when you travel in china, remember to change us dollars for rmb. 24. repair 【动词】修理，修补； fix【动词】安装；使固定 【fix up 修理=repair】unit3 could you please clean your room 1. peter ,could you please take out the trash 彼得，你能把垃圾倒了吗 could you please do sth 请你（做）......好吗 用于提出请求，希望得到对方的肯定回答，说话的语气比较客气委婉。 could 不是 can 的过去式，是委婉、礼貌的说法。回答用 can. 【常用答语】肯定回答：sure./ of course./ certainly./no problem. 否定回答： sorry , i can’t 2、take out 取出（v+ adv） 【注】: 跟代词做宾语，代词放中间； 跟名词做宾语，可放在中间，也可放在后边 his teeth hurt badly. the dentist take them out . 【短语】take out the trash 倒垃圾 take a walk 散步 take away 拿走，取走 take back 收回 take place 发生 take off 脱下； 起飞 3. can you do the dishes.那你可以洗盘子吗 do the dishes 洗碗 【结构 1】do the +名词： do the dishes/ laundry 洗餐具/衣服 【结构 2】do the +动词-ing do the cleaning 打扫卫生 【结构 3】do one’s + 名词 do one’s housework/ homework 做家务/家庭作业 【结构 4】do some +动词-ing do some reading/ shopping 读写书/购物 4、could i at least finish watching this show 至少让我看完这个节目可以吗 1】could i do a sth 我可以做......吗 用于表达请求，语气比较委婉。 could i go out with my classmate this weekend 2】at least 至少，多指数量或程度上的最低限度。(反) at most 至少，不超过 now all of us exercise at least an hour a day and outside school. 3】finish v 结束；完成 finish doing sth 做完某事 — can you finish __reading__ these books before 10 o'clock — yes, i can. 5、i think two hours of tv is enough for you!5我觉得你看两个小时的电视已经足够了。 1】two hours of tv 表示时间、距离、金额、度量等词语作主语时，通常被视作整体，谓语动词用单数形式。 how time is flies! three years __is_____(be) really a short time.【解析 2】enough作 形 容 足够的，充分的（在句中作定语或表语） 词 i don’t have enough money with me. 作 副词足够；充分（放在形容词；副词后） the river is deep enough for swimming. 【记】 mr. smith has enough money ,but he isn’t kind enough to help others. 【注意】enough 修饰名词时，置于名词前；修饰形容词时，置于形容词之后。 6、could you take out the rubbish,fold the clothes and do the dishes 你能把垃圾倒了。把衣服叠好，再把碗洗了吗 【解析】take out 拿出；取出 take 的用法： please take some books to the classroom. 拿；取 吃；喝；服用 take 乘（车；船等） they usually take the bus to work.take this medicine three times a day.it takes me two hours to do my homework every day. 花费（时间；金钱） 【拓展】take 构成的短语： take a walk 去散步 take a rest 休息 take care of 照顾 take off 脱下；起飞 take up 占据 take down 拿下 take one’s time 不急；慢慢来 take one’s temperature 量体温 7. the minute i sat down in front of the tv, my mom came over . 我刚坐在电视机前面，我妈妈就过来了。 【解析 1】the minute = as soon as ―一...... 就......‖ please write to me the minute you get there. 【解析 2】 in front of 指在物体外部的前面 in front of there is a bike in front of the classroom. 【辨析】 in the front of 指在物体内部的前面 our teacher is standing in the front of the classroom【记】 the driver sat _____in the front of___________ the car. the policeman stood ___in front of________ the car. 【注意】有 the 无 the 区别大： at table 吃饭；进餐6at the tabel 在桌边 in hospital 住院 in the hospital 在医院（不一定看病） 【解析 3】come over 过来 【拓展】 come 短语： come across（偶然）发现 come back 回来 come up with 想出 come true 实现 come down 下来 come from=be from 来自,出生于 come in/into 进入,进来 come on 赶快,加油 come along 走吧,过来,快点 come and go 来来去去 come up 上来 come out 出来，(花)开，(照片)冲洗出来 7. you watch tv all the time and never help out around the house! 你总是看电视，从不帮忙做家务！ all the time = always 一直；总是 8. i’m just as tired as you are! 我和你一样累！ 【解析】as...as ... 和......一样...... 9. for one week , she did not do any housework and neither did i. 一周的时间，她不做任何家务，我也不做。 【解析】neither +助动词/系动词/情态动词 +主语 “某人（主语） 也不” ⑴neither 两者都不 neither …nor… 既不…也不…, 连接两个词做主语，谓语动词由后一个主语确定 neither tom nor jim is a student ⑵ 表达“…也不……” 则用 “neither /nor + be / v 助 / v 情 + 主” —the first one wasn’t bad. — neither was the second. 10. the next day , my mom came home from work to find the house clean and tidy. 第二天，妈妈下班回到家后发现房间很干净、整洁。 【解析】find +宾语+宾语补足语 【注】find → found →found v 寻找 (1) find sb. doing sth 发现某人做某事 (2) find it + adj. + to do sth 发现做某事很…… ◆ find it difficult/ hard to do sth 发现做某事很困难 she found _it__ hard to finish the work by herself. 11. she asked in surprise.她吃惊地问道。 【解析】in surprise 惊奇地；吃惊地 surprise v 使吃惊→surprising adj. 令人吃惊的 →surprised adj. 吃惊的 to one’s surprise 使某人吃惊的是 in surprise 吃惊地 be surprised at 对……感到吃惊 to my surprise_(使我吃惊的是） ，he got the first prize in the exam. 12. “ i’m do sorry, mom. i finish understand that we need to share the housework to have a clean and comfortable home.” i replied. “对不起，妈妈。我终于理解为了拥有一个干净、舒适的家我们需要共同来分担家务。” 我回答说。 【解析 1】need v 需要 用于肯定句，是实义动词。 (1)人做主语，sb. need to do sth 某人需要做某事 (2)物做主语，sth need doing sth= sth need to be done7① students need ___to have_______(have) a good rest in studying. ② the watch needs__mending___(mend).用于否定句或疑问句，是情态动词 (1)needn’t = don’t have to 没有必要 (2)need ,must 引导的一般疑问句，肯定会的用 must,否定回答用 needn’t — must i go there now — yes，you must/no, you needn’t 【解析 2】share 分享；共用 share sth 分享或共用某物 share sth with sb. 与某人分享某物 (all his friends __shared___ his happiness when he won the match. 13.could i hang out with my friends after the movie 看完电影后我能和朋友们一起闲逛吗 【解析】hang out 闲逛 hang up 把......悬挂/挂起 14. could you please pass me the salt你能把盐递给我吗 【解析】pass ⑴ v 给；递；走过；通过 pass sb.sth 把某物递给某人 pass on 传递 please pass the paper on to the other students. ⑵v 通过；路过 i pass your home. ⑶v 通过（考试） ；及格 tom can pass his math exam. 15. could i borrow that book我能借下你那本书看吗、 could you lend me some money你能借我一些钱吗 【解析】borrow /lend/keep (1)borrow 借入 ,与 from 连用，尤指主语―【借进来‖】 borrow sth from sb. 从某人那里借某物 you can borrow the book from the library. (2)lend 借出 ,与 to 搭配 【指借出去】 lend sb sth=lend sth to sb 把某物借给某人 he doesn’t want to lend his book to others. (3)keep 保留，保存（延续动词，可以与表示一段时间的状语连用） 【指借一段时间】 【记】 i want to __borrow__ a bike from my friend but he didn’t _lend___ it to me, because tom had _kept____ it for two days. 16. i cut my finger and i’m trying not to get it wet. 我的手指割伤了，伤口不能弄湿。 【解析】try (not) to do sth 努力（不）做某事。 try v 试图，设法，努力 (2) try to do sth 努力做某事 【侧重尽力做】 (3) try doing sth 试图做某事 【侧重尝试做】 (4)try one’s best to do sth= do one’s best to do sth 尽某人最大努力做某事 17. i hate to do chores. 我讨厌做家务。 hate to do sth 讨厌做某事, 表示某次具体行为或动作。 i hate to trouble him. hate doing sth 不愿意做某事 表示经常或习惯性行为或动作。 she hates smoking in her room.8【拓展】 (1)try on 试穿18.could i ask you to help me with some chores then 那我能请求你帮我做些杂活吗 【解析】ask sb. to do sth 要求某人做某事。 ask for 请求，要某物 ask sb. about sth 向某人询问关于某事 (1)ask sb. for help 向某人请求帮助 (2) ask sb. (not) to do sth 请求某人做某事 ask 构成的短语： 短语 ask sb. to do sth ask sb. not to do sth ask sb for sth ask for help 含义 请某人做某事 不让某人做某事 向某人要某物 寻求帮助19.i’ll finish my homework while you help me with the dishes. 当你帮我洗盘子的时候，我将完成我的家庭作业。 【解析 1】finish doing sth 完成某事 — can you finish _reading__ these books before 10 o’clock — yes, i can. 【解析 2】while conj. ―在……期间； 当……的时候‖ while 引导的时间状语从句的谓语动词只能是延续动词。 _while __ the children have fun, parents can take dance lessons on the beach. 【解析 3】help sb. with sth. 在某事上帮助某人。 【注】help v 帮助 → helpful adj. 有帮助的 (1)help sb. do sth. =help sb. with sth. 帮助某人做某事 (2)with the help of sb.=with one’s help 在某人的帮助之下 (3)without the help of 没有在…的帮助之下 ① i think reading is very __helpful____(help). ②__without____ your help, we couldn’t catch the thief. 20. could i invite my friends to a party 我能邀请我的朋友们来聚会吗 【解析】invite sb. to sp. 邀请某人去某地 【解析】invite v → invitation n 邀请 (1) invite sb. to do sth 邀请某人做某事 (2)invite sb. to +地点 邀请某人去某地 21.i don’t understand why some parents make their kids help with housework and chores at home. 我不理解为什么有些父母在家让孩子们帮忙做家务和杂务。 【解析】make sb. do sth 让某人做某事 make → made →made v. 做， 制作， 使得 (1) make sb/sth + 形容词 ―让某人或某物…‖ make you happy make me laugh. (2) make sb/sth do sth 使某人做某事colors can change our moods and make us _feel__ happy or sad, energetic or sleep. 22.they don’t have time to study and do housework，too.9他们也没有时间来学习家务和做家务。 【解析】have time to do sth.有时间做某事 have time =be free 有空 23. housework is a waste of their time. 做家务是在浪费他们的时间。 【解析】a waste of 浪费 a waste of time 浪费时间 a waste of money 浪费金钱 waste v ―浪费‖ waste time/money on sth waste time / money (in) doing sth 在做某事上花费时间/金钱 don’t ____waste______water. can’t you see the sign ―save water‖ 24.they should spend their time on schoolwork in order to get good grades and get into a good university. 为了取得好成绩并考上一所好大学，他们应该把时间用在学习上。 【解析 1】spend... on sth 在某事上花费...... spend/pay/cost/take 花费 (1)spend→spent→spent v 花费,主语是人 ◆sb.+ spend +时间/钱+on sth ◆ sb. +spend +时间/钱+（in） doing sth ◆ spend on= pay for 支付 he spends too much time on the computer games. remember to spend some time _with_ your loved ones, because they’re not going to be around forever. my father __spent___ one hundred thousand yuan on his new car. (2) pay →paid →paid v 支付，主语是人 ◆ sb.+ pay + 钱+for sth — five hundred dollars. (3) cost→ cost→ cost v 花费，主语是某物或某事 ◆ sth cost sb. +钱 某物花费某人多少钱 a new computer costs me a lot of money. i bought a new sweater last weekend. it ___cost_ me 120 yuan. (4)take→took → taken v 花费 ◆ it takes /took sb. some time to do sth. 做某事花费某人多长时间 it takes him 3 hours to do his homework. 【解析 2】in order to ―目的是；为了‖ 后接动词原形。 in order to do sth 为了做某事 he ran quickly in order not __to be___ late for the meeting. 【解析 3】get into =enter 进入 【拓展】与 get 相关的短语： get up 起床 get back 返回 get over 克服 get dressed 穿衣 get into 进入 get/be lost 丢失 get off/on 下/上车 get on well with sb.与某人相处得好 get out of 从…出来 get warm 变暧 get ready for +n.为…做准备 get ready to do sth.准备做某事 get well 康复 get a chance 有机会、得到机会 get/go to sleep(fall asleep)入睡 相关：(be asleep 睡着) 25.also,when they get older, they will have to do housrwork so there’s no need for them to do it now. 而且，当他们长大的时候，他们也将会做家务，因此，他们没必要现在在做。10i pay 10 yuan for the book.— how much did you __pay__ for this computer【解析】get older 长大 get/ become/ go 辨析： ⑴get+adj 较多地与形容词比较级连用。 the days are getting longer and longer. ⑵ become 强调变化的结果 it's becoming colder and colder. ⑶ go+adj.''表示令人不快的事情 go bad 变坏，go blind 变瞎，go hungry 挨饿 26. it is the parents’ job to provide a clean and comfortable environment at home for their children. 在家 为孩子们提供一个干净、舒适的环境是父母的义务。 【解析】provide sth. for sb. 为某人提供某物 provide v 提供 provide sb. with sth. (sb 前介词用 for) =provide sth for sb.( sth 前需加介词 with)供应某人某物 相当于：offer sb. sth. = offer sth to sb.provide offer supply为应急等做好准备而“提 供； 供给” 侧重表示“愿意给予” 定期 “ 供应 ” , 强调替代或 补充所需物品provide sb. with sth. =provide sth for sb.提供某人某物 offer sb. sth. = offer sth to sb. 对某人提供某物 offer to do sth 主动提出干某事 supply sb. with sth=supply sth. to sb. 为某人提供某物① the internet provides us _with__a lot of _information___we need. ②—could you please provide us _with___ some information about the students’ health— of course, it’s my pleasure. 27. and anyway, i think doing chores is not so difficult. 无论如何，我认为做家务并不那么难。 【解析】anyway 无论如何, (一般放在句首，用逗号和句子隔开） 28. i think it is important for children to learn how to do chores and help their parents with housework. 我认为对孩子们来说，学习如何做杂务并帮助他们的父母做家务是很重要的。 【解析】it is important for sb. to do sth. 对某人来说做某事是重要的 29. children these days depend on their parents too much. 现在的孩子太依赖他们的父母。 【解析】depend on 依靠；信赖 —— shall we go for a picnic tomorrow —— well, it all ___depends on____ the weather. 30. ... everyone should do their part in keeping it clean and tidy. 每个人都有责任保持家里的干净和整洁。 【解析 1】 do one’s part 尽职责；尽本分 do one’s part in doing sth 在做某事上尽职责11【解析 2】keep +sth /sb. +adj. ―使......处于某种状态‖ her mother asked her to keep the windows __open__ and the door __closed__. keep 系动词 ―保持‖ keep + adj . we must keep healthy. 实义动词 ―保持；继续‖ (1) keep ( on ) doing sth 继续做某事 he was in great pain but he kept on working he kept on __ talking__ after the ball rang for class. (2) keep sb. doing sth 让某人一直做某事 i’m sorry to have kept you waiting for so long. my teacher kept me __doing___ homework all the afternoon. 31. doing chores helps to develop children’s independence and teaches them how to look after themselves. 做杂务不仅可以培养孩子们的独立性还可以教 他们如何照顾自己。 【解析】develop independence 培养独立意识 develop v→development n 发展→developing adj. 发展的 →developed adj. 发达的 a developing country 一个发展中国家 a developed country 一个发达国家 china is a __developing___country. 32. since they live in one house with their parents, they should know that everyone should do their part in keeping it clean and tidy. 既然他们和父母同住在一个房子里，他们应该知道保持家里干净、整洁每个人都应该参与。 【解析】since conj. 既然 (表示对方已知的事实或理由，常放在句首） .—you have been in neijiang very long —yeah. __since___my parents came here. 33. our neighbor’s son got into a good college but during his first year, he had n idea how to take care of himself. 我们邻居的儿子上一所好大学，但是在第一年的时候，他还不知道如何照顾自己。 【解析】take care of 照顾 thanks for your invitation, but i’m so sorry i can’t go. i need to ___take care of___ my baby at home. 【拓展】与 take 相关的短语： take photos/pictures 照像 take away 拿走 take out 取出(work out 算出) take care 当心 take medicine 服药 take place 发生 take one’s temperature 量体温 take one’s time 别着急 take a walk 散步 34. as a result , he often fell ill and his grades dropped. 结果，他常常生病，功课也落下了。 【解析 1】as a result 结果 （插入语，放在句首，用逗号隔开） don’t ask him too late into the night, __as a result___ , he is only a small child. 【解析 2】fall ill 生病 fall asleep 入睡 35 .the earlier kids learn to be independent , the better it is for their future. 孩子们越早学会独立，对他们的未来越好。 【解析】the + 比较级， the + 比较级 ―越...... 越...... ‖ the more you smile, the ___ happier____ you will feel.12unit 4 why don’t you talk to your parents 一、基础知识 1. why don’t you talk to your parents 你为什么不和你打父母谈谈呢 【解析】why don't you do sth = why not do sth 为什么不......呢 【拓展】用于提建议的句型有： (1)what about doing sth =how about doing sth ….怎么样 (2)why don’t you do sth= why not do sth 为什么不呢 (3)let’s do sth.让我们一起做某事吧。 (4)shall we/i do sth我们做…好吗 (5)had better do/not do sth 最好做/不做某事 (6) will/would you please do sth 请你做…好吗 (7) would you like to do sth 你想去做某事吗 (8)would you mind doing sth你介意做某事吗 【回答】 (1). 同意对方的建议时，一般用： ◆good idea./ that’s good idea. 好主意 ◆ ok/ all right./ great 好/ 行/太好了 ◆yes, please ./ i’d love to 是的/ 我愿意 ◆i agree with you 我同意你的看法 ◆no problem 没问题 ◆ sure/ of course/ certainly 当然可以 ◆ yes, i think so 对，我也这样想 (2).对对方的帮助或要求表示委婉谢绝时，一般用： ◆i don’t think so 我认为不是这样 ◆ sorry, i can’t 对不起，我不能 ◆ i’d love to, but… ◆i’m afraid…我愿意，但恐怕…… 【2013 天津 4】35.— why not go to lao she teahouse tonight — ______. a. it doesn't matter b. thank you c. sorry to hear that d. sounds great 【2013 广东广州 4】25.—i feel really tired. —______ a. lucky you! b. you’d better work harder. c. congratulations! d. why not go and have a rest 【2013 四川凉山 3】37. —it’s a nice day, isn’t it —yes. ______ going hiking and relax ourselves a. why not b. why don’t c. what about 【2013 湖南益阳】you look too tired. why not _____ a rest a. stop to have b. to stop having c. stop having 2. i have to study too much so i don’t get enough sleep. 我要学的太多，因此我睡眠不足。 【解析 1】(1)too many + 复数名词 许多 too many people (2)too much +不可数名词 许多 too much homework (3)much too +形容词 太… much too cold13【2013 山东德州 1】— what’s the matter — i have a stomachache. maybe i have eaten ___ tonight. a. too much b. too many c. much too 【解析 2】so conj. 因此 (表示因果关系，后面跟表示结果的句子，不与 because 同时使用） 【2013 浙江舟山、嘉兴 1】18. the shops were closed_______ i didn't get any milk. a. so b. as c. or d. but 3. my parents don’t allow me to hang out with my friends. 我的父母不允许我和我的朋友们出去闲逛。 【解析】allow sb. to do sth 允许某人做某事 【拓展】allow v 允许 allow doing sth 允许做某事 they don’t allow smoking. allow sb. to do sth 允许某人做某事 my mother allows me to watch tv. be allowed to do sth 被允许做某事 ① we don’t allow ___________(smoke) in the reading room. ② our teacher allows us ____________(go) out for a walk. ③ the boy should be allowed____(play) after supper. ④ we won’t allow ________in the cinema .but you are allowed ______in the rest room.(smoke) ⑤ teenagers should ___________ (allow) to choose their own clothes. 【2013 辽宁鞍山 3】 25. —can i smoke in the dining hall —sorry. it's not_________. a. promised b. realized c. allowed d. reminded 【拓展】allow 与 let 的辨析： allow 指“允许”，表示“默许，听任，不加阻止”， allow sb to do sth 允许某人做某事。 let 指“让”，let sb do sth 让某人做某事，语意较弱，多用于口语中，let 不能用于被动语态。 4. what’s wrong 怎么啦 【解析】what’s wrong( with sb./ sth) （某人/物） 怎么了 【2013 四川南充】— mum , i’m not feeling well. — oh, dear! _____. a. what’s wrong b. not at all c. all right. 5. i’m really tried because i studied until midnight last night. 我真的很累，因为我昨天晚上一直学习到半夜。 【解析】until 直到......时 【2013 山东临沂 2】23. please hold on to your dream _____ one day it comes true. a. if b. until c. unless d. though 【2013 山东青岛 3】13. if you have trouble pronouncing these words, you can repeat them over and over again ______ you are comfortable with them. a. unless b. if c. until d. while 【2013 浙江丽水 3】18. —hey, man. you can’t cross the street now. you have to wait _____ the traffic turn green. —oh, sorry and thank you. a. when b. after c. until d. while 6. why don’t you go to sleep earlier this evening14今天晚上你为什么不早点睡觉呢 【解析】go to sleep 去睡觉 (强调“入睡，睡着”这一动作） 7. you look sad, kim. 金，你看起来很伤心。 【解析】look 看起来 （系动词，后跟形容词作宾语） 【2012 江苏苏州 3】some of friends eat with their eyes. they prefer to (更喜欢） what ____ nice. a. feels b. smells c. looks d. tastes 【拓展】 ：系动词：后跟 adj. 作表语 一是： （be） am /is /are be quiet=keep quiet 保持安静 二保持：stay/keep （表示持续状态） stay healthy=keep healthy 保持健康 三变化：become/get/turn （表示状态变化） 五起来：sound/look/smell/taste/feel （表示感觉） ( )jack usually gets ______ when he speaks in public. a. happily b. exciting c. worried d. tired ( ) tom’s father looks very _____. but he is very kind. a. seriously b. serious c. friendly 8. you ____ call him up. 你____ 给他打电话。 【解析】call up (v + adv) call on 拜访；号召 i call up my parents every sunday. 9.well, i found my sister looking through my things yesterday. 哦，昨天我发现我妹妹翻了我的东西。 【解析 1】find sb. doing sth 发现某人正在做某事 mr. wang found li dong reading a storybook in the class. 类似动词：hear，watch, see, feel 【贵州安顺】when i went into the room, i found ___ in bed. a. him lying b. he lying c. he lies d. him was lying 【解析 2】look through 浏览 【拓展】与 look 相关的短语： look for look after=take care of look like look the same look over look through look out look up look around look forward to 【2013 四川泸州】9. can you help me to _______ my dog when i leave for hong kong a. look after b. look fo c. look at d. look through 【2013 湖北十堰】30. here is the book. first _________ it and then tell me what you think of it. a. look into b. look through c. look up d. look after 10. yes, but i’m still angry with her. 是的，但是我仍然很生她的气。 【解析】be angry with sb. 生某人的气 【拓展】angry adj. 生气的→ angrily adv. 生气地 (1)be angry with sb. =be mad at sb. 对某人生气【with 后接人】 (2)be angry at/about sth 对某事感到生气 【at 后接事】 (3)be angry to do sth 做某事感到生气 【记】 my father was very __________(对……生气)his computer. he hit the computer _______(angry)15) — why are you unhappy, kate — i didn’t finish my homework again. i’m afraid miss gao will be ___ me. a. angry with b. friendly to c. proud of ( ) i was very angry ____ myself ___ making such as a stupid mistakes. a. at b. for c. with d. at 【2013 枣庄】88. i got home for my birthday from my college on friday evening. no one was at home, and mom and dad hadn’t left me a note. this made me _________. a. surprised b. happy c. angry d. excited 【2013 吉林 3】103. i felt sorry that i dropped the juice on tina’s bed. but she wasn’t _____ at all. a. excited b. happy c. angry 11.although she’s wrong, it’s not a big deal. 尽管她错了，但也不是什么大错。 【解析 1】although= though 尽管 , 用来引导让步状语从句。 【注】though / although 不能与 but 连用 【2012 曲靖中考】 ____ my father isn’t pleased with his working environment , he still works hard. a. and b. although c. but d. before 【2013 福建福州 3】41. — the boy can speak both english and japanese _________ he is only ten. — wow, what a clever boy! a. if b. because c. although 【2013 浙江宁波 3】32. —look! some people are running the red lights. —we should wait _______ others are breaking the rule. a. if b. unless c. although d. because 【拓展】although/however 辨析 ⑴ although conj，“虽然；即使；纵然”，引导让步状语从句时放在主句前后都可。 although he is very old, yet he is quite strong.他虽然年纪大了，但身体还很健壮。 ⑵however adv，在句中作插入语，起一个连词的作用，一般用逗号与句子分开，可以放在句首或句中， 意为“然而，尽管如此”。 it’s raining hard, however, i think we should go out. 雨下的很大。尽管如此，我认为我们还应该出去。 【解析 2】it’s not a big deal. 没什么大不了；不是什么大事（常用于口语中） ( you left your homework at home. 你把作业忘在家里了。 【解析】leave v 遗忘，留下 leave sth . somewhere 把某物忘在某地 leave sb. by oneself 把某人单独留下 【2012 山东济宁】22.—sorry, mr. green. i have ____ my homework at home. —never mind. but don't forger next time. a. put b. kept c. left d. remained1612. hope things work out. 希望事情顺利解决。 【解析 1】hope v 希望 hope to do sth i hope to visit guilin. hope + that 从句 （表示希望） i hope that you’ll be better soon wish v 希望 wish to do sth i wish to visit guilin. wish sb.to do sth 希望某人做某事 i wish you to go. wish +that 从句 表示愿望，从句用虚拟语气 i wish i were you. 【解析 2】work out 解决；成功地发展，后跟 fine,well, badly 等词，表明产生的结果如何。 计算出（答案、数量、价格等） the math problem is too difficult for me to work out work out 制定出（计划等） i have worked out a new way of doing it. 解决；找出…的答案 the government has many problems to work out. 【2013 四川遂宁 3】30. the teachers encourage their students to ____ the problems by themselves, and in this way students can enjoy success. a. give up b. work out c. look through 13.my problem is i can’t get on with my favorite. 我的问题是我不能喝我的家人和睦相处。 【解析】get on with sb. 和某人和睦相处；和某人关系良好 =get along with get on well/ badly with 相处的好/坏 【2013 山西 1】26. a student in fudan university was killed by his roommate just because of small things in daily life. it is important for students to learn how to ________ each other. a. get on with b. come over to c. stay away from 【2013 湖北十堰】32. —what kind of persons do you prefer to make friends with —i choose my friends on their characters and how we __________. a. get in b. get up c. get on d. get off 14.when they argue, it’s like a big, black cloud hanging over our home. 当他们争吵的时候，就像有一大团乌云笼罩在我们家。 【解析 1】argue 争吵 →argument n 争论 have an argument with sb.与某人辩论 argue with sb. 与某人争吵 argue with sb. about sth 为某事与某人争吵 argue about sth 争论某事 argue against 争辩；反对 he argued against the plan 【2013 辽宁锦州】11. —he looks unhappy today. —let’s _______. a. cheer him up b. help out him c. look him after d. argue with him17【解析 2】 hang over 挂在......之上； 悬浮在......之上 hang out 闲逛；常去某处 he likes reading and he often hangs out in the bookshop. hang on to 紧紧抓住 you’d better hang on to me in the crowd. hang up 挂电话；悬挂 after she finished her conversation 15.also, my elder brother is not very nice to me. 【解析】elder adj.年纪较长的 his elder brother is ill. elder older 用来表示兄弟姐妹及子女之间的长幼关系，常用作定语 泛指新旧、老幼或年龄的大小关系，可以用作表语，是 old 的比较级形式。【记】 my ______brother is 7 years older than my younger sister. 【2013 南京 2】i’m surprised that john is only 25. i thought he was ________ , for he seems to be in his thirties. a. old b. older c. young d. younger 【解析 2】be nice to sb. 对某人友好 be friendly to sb. be good to sb. 16.he always refuses to let me watch my favorite tv show. 他总是拒绝让我看我最喜欢的电视节目。 【解析】refuse =say no to v 拒绝 refuse to do sth 拒绝去做某事 ① the boy refused __________(go) to see his father with us. ( )② he refused when i asked him for help.a. said yes b. said no c. said hello 【2013 浙江宁波】74. he invited her to his birthday party but she _______(拒绝). 17.instead he watches whatever he wants until late at night. 相反，他却想看什么酒看什么， 一直到深夜。 【解析 1】 instead 代替，反而，替 (1) instead 副词，代替，常放在句首或句尾,表示前面的事情没做，而做了后面的事情。 lee was ill so i went instead.李病了，所以我去了。 (2) instead of +n/doing 代替，而不是，放在句中 instead of 为介词短语，后面一般接名词、代词、介词短语或动名词形式。 she wrote to him instead of calling him .=she didn’t call him. she wrote to him instead. 她没有给他打电话，而是给他写了封信。 ( ) health is very important to us. we should eat more vegetables and fruit _____ rich food. a. instead b. instead of c. because of d. because 【2011 江苏徐州 4】14. we’ve got no coffee. let’s have tea _______. a. either b. however c. yet d. instead 【2013 江苏盐城】59.to keep fit, we should have more vegetables and fruit _________(代替) of too much meat. 【解析 2】 whatever = no matter what 任何，每一 【2013 甘肃兰州】_________ happens, i won’t change my mind.(无论什么）1818.if your parents are having problems, you should offer to help. 如果你的父母有问题，你应该主动提供帮助。 【解析】 offer to do sth 主动提出做某事 【拓展】offer v 主动给予 (1) offer to do sth 主动提出做某事 (2)offer sb. sth= offer sth to sb. 主动提供给某人某物 ( )the little boy _____ his seat to the old lady on the crowded bus.a. offered b. brought c. lent d. took 【2013 山东莱芜 2】27. the little boy ________ his seat to an old lady on the crowded bus. a. lent b. offered c. took d. brought 19.secondly,why don’t you sit down and communicate with your brother 其次，你为什么不能坐下来和你的哥哥交流一下呢 【解析 1】secondly adv.第二；其次 【解析 2】communicate v 交流 communication n 交流；沟通 communicate with sb. 和某人交流 they communicate with each other by qq. ( ) they can’t understand each other so they have difficulty in _____. a. communicate b. communicated c. communicating 20.you should explain that you don’t mind him watching tv all the time. 你应该跟他解释说你并不介意他一直看电视。 【解析】explain 解释；说明 → explanation n 解释；说明 explain sth to sb. 向某人解释某事。 explain to sb sth 给某人解释某事 【江苏扬州】mr. wu always spends a lot of time __________(解释) things to us. 【2012 浙江宁波】22. —do you ________that nancy has been a little too quiet these days —yes. she didn't even say a word this afternoon. a. hope b. notice c. explain d. decide 21. i’m worried about my school grades. 我很胆小我的学习成绩。 【解析】 be worried about sth. 担心某事 【拓展】worry v 担心 → worried adj. 焦急的 worry about = be worried about 为……担心 (① don’t be _________(worry). you’ll catch up with others. )②don’t ____ about things so much. it will make you stressed out.a. afraid b. worry c. worried d. terrified 【2013 绍兴】91. －you look _________ . what's up, sir －i can't find my ticket, but it's time to check in. a. sleepy b. hungry c. tired d. worried 22.my cousin borrows my things without returning them. 我堂弟借我东西没有还我。 【解析】return ⑴ v 归还=give back return ... to ... = give back to ... 把......还给...... ⑵v 回来；返回 = come back 【2012 浙江宁波】he borrowed my iphone 4 and didn’t ________(归还） it to me.1923.my parents give me a lot of presure about school. 我父母在学习上给了我很多压力。 【解析】press v 按；压 →pressure 压力 ⑴ 不可数名词 （物理学）压力 air pressure 气压 blood pressure 血压 ⑵ 不可数名词 还可指精神上、外界施加的压力 = stress under pressure 在压力下 24.i have to compete with my classmates at school. 在学校我不得不和我的同学们竞争。 【解析】compete v 竞争；对抗 → competition n 竞争 compete with sb. 和某人竞争 compete against/ with 与……竞争 compete for 为……参加比赛 we are ready for the coming ________________(compete). 25.you should all be ___ each other to improve. 你们都应该互相____ 而全面发展。 【解析】improve =make ... better 改进 →improvement n 提高 26.who gives their opinions about the problem 对于这个问题都有谁提出了他们自己的观点。 【解析】opinion n 意见；想法；看法 in one’s opinion 以某人的观点；在某人看来 give opinions about sth. 给出关于某事的观点。 27.these days , chinese children are sometimes busier on weekends than weekdays because they have to take so many after-school classes .目前，中国的孩子有时周末比平常还要忙，因为他们不得不上那么 多的课后辅导班。 【解析】some time /sometime/some times/sometimes 【口诀】 ：分开是一段， 合起是某时； 分开 s 是倍次，合起 s 是有时 (1) some time 一段时间，做时间状语 it takes sb. some time to do sth. 做某事花费某人多长时间 (2) sometime adv 在某个时候， (3) some times 名词词组，“几次，几倍” mr. green went to sanya some times last summer. (4)sometimes=at times 有时 （一般现在时的标志词） ( ) i hope to visit the usa _____ in the future. a. sometimes b. some times c. sometime d. some time 【2013 广西】 at times an ad can lead you to buy something you don’t need at all. so you have to be careful. a. sometime b. sometimes c. some time d. some times 28. others are practicing sports so that they can compete and win. 其他人正在练习体育运动， 这样他们就能参与竞争并获胜。 【解析】 others pron. “其他的人或事物” there are other ways of doing it. 做这事还有其他的办法。 ( ) my sister is outgoing . she likes making friends with ____. a. other b. another c. the other d. others2029.the taylors are a typical american family. 泰勒一家是一个典型的美国之家。 【解析 1】the taylors 泰勒一家 。 在姓氏的复数前加冠词 the 表示“全家人或夫妻两人”，使用时注意 主语和谓语保持一致。 the blacks are getting ready for the holiday. 【2012 广东】____ greens are preparing for the coming thanksgiving day. a. / b.a c. an d. the 【解析】typical 典型的 be typical of ―是……的特点‖ 30.. maybe i could cut out a few of their activities, but i believe these activities are important for my children’s future. 或许我可以减少他们的一些活动， 但是我相信这些活动对孩子们的未来很重要。 【解析】cut out 删除；删去 (v+adv) you’d better cut out that sentence. cut up 切碎 cut down 砍到 cut in 插队 cut off 切断（水、电）供应 ( ) don’t ___ it’s impolite. a. cut out b. cut in c. cut down d. cut off 31. i really want them to be successful. 我真的很想他们成功。 【解析】successful 成功的 【拓展】 succeed v 成功，达到 →success n 成功 →successful adj 成功的 →successfully adv 成功地 ◆ succeed in doing sth ① if at first you don’t ____________(success) . try, try again. ( )②she works very hard ,so she will ____ in ____ the exam. a. pass b.passing c. passing d. passing 【2013 甘肃兰州】87. details decide ______ (成功) or not. if we take everything seriously, we’ll achieve our goals. 【2013 贵州铜仁】85.—what’s the secret of your ________（success） —work hard. 【2013 四川凉山】85. after hundreds of experiments, edison _______ (成功) invented the light bulb. 【2013 山东青岛 3】12. it is ______ that mr. guo sailed across the world by himself ______ within about 130 days a. terrified, successful b. scary, successfully c. amazing, successfully d. convincing, successful 32.it’s time for homework.该写作业了。 【解析】it’s time for sth 是到做某事的时候了。it’s time for lunch. it’s time to do sth it’s time to go to school. ( ) it’s 9:30 pm., children! _____ is time to go to bed. a. that b. it c. this d. they 33. in some families, competition starts very young and continues until the kids get older. 在有些家庭，竞争从孩子们很小的时候就开始了，一直持续到他们长大。 【解析】continue 继续；持续21【拓展】continue doing sth =go on doing sth 继续做某事(前后做同一件事) continue to do sth = go on to do sth 继续做某事（前后不是同一件事） ① let’s continue____________(read) the text. ② many students hope to continue ________ (study) after _______(finish) school. （ ）③the two teams continued _____ the game after half an hour. a. play b. to play c. playing d. played 【拓展】continue，go on, last 辨析 ⑴ continue v.继续，持续，指进程在时间或空间上的延续，强调持续不断，有时也可以指短暂停止后继 续进行。 he continue the work for two days.他连续两天都在做这项工作。 ⑵go on 指无间歇或有间歇地继续，或以某种特定方式继续。 go on to do sth 继续做某事，指开始做另外一件事； go on doing sth 继续做原来所做的事情。 after doing his homework, he went on to preview his lessons. 做完家庭作业之后，他继续去预习他的研究。 ⑶ last v.持续，延续，维持，指某事物继续存在或某种现象在时间上延续，说明某一动作要延续一段时 间。 she won’t last long in that job.那个工作她做不了多久。 34.mothers send their small kids to all kinds of classes. 妈妈们把她们的小孩子送去各种各样的辅导班。 【解析 1】send→ sent → sent v 发送 【短语】 ： send away 赶走 send for 派人去请 send off 寄出 send out 分发 send up 发射 send sb. sth = send sth to sb. 送给某人某物 【注】类似的动词有：show (展示； 给……看) give (给) lend (借出) offer（提供） return （归还） tell （ 告诉） ( ) ①you fill in both parts of the form, then_____. a. send up it b. send for it c. send it away d. send it off ( ) please send a photo of your family ____ me. a. for b. at c. to d. with 【2011 四川绵阳】15. ---- drunken drive is dangerous, isn’t it ---- yeah. that why drunken drivers_____ to prison even without causing accidents. a. sent b. are sent c. send d. are sending 【解析 2】all kinds of 各种各样的 【拓展】kind (1) n 种类 kind of +adj.有点，有几分，kind of cold 有点冷 a kind of 一种的，某种的 all kinds of 各种各样的 different kinds of 不同种类的 what kind of…那种 (2) adj. 友好的 be kind to sb. = be good to sb.=be friendly to sb. 对某人友好 【辨析】kind of 与 kinds of: 1 kind of 单独用，表示“有点”，后接形容词或副词： ○ he is kind of thin.‖他有点瘦‖ i feel kind of hungry.‖我有点饿‖22uncle wang speaks kind of quickly. 王叔叔说得有点快。 2 若 kind of 前有 a, this, that, what 等，译为“种，种类” 后加名词。 ○ that kind of question is difficult to answer. 那类问题难回答。 what kind of sport do you like best 你最喜欢何种运动 ( )① this kind of skirt looks ___ and sells _____. a. well b. good c. well d.nice ( )② —what ____ animals do you like — monkeys. i think they’re _____ clever. a. kind of b .a kind of c. a kind d. kind of ( )③— it’s going to rain. let me fetch an umbrella for you. — thank you ! you are so ____. a. lucky b. kind c. relaxed d. interesting 【2013 浙江台州】17. —i want to see the movie iron man 3 (《钢铁 3》). do you know the ______ of the ticket —yes. five dollars. a. number b. price c. kind d. name 35..kids should have time to relax and think for themselves, too. 孩子们也应该有时间放松和独立思考。 【解析】have time to do sth 有时间做某事 ( ) do you have time _____ this game with us a. to play b. play c. playing d. played 36. and they are always comparing them with other children. 她们总是把自己的孩子和其他的孩子作比较。 【解析】compare a with b 将 a 和 b 比较 (1)compare…with… 把……与…..做比较 (2) compare…to… 把…..比做…… ( )① . people often compare a teacher a candle. a. to b. into c. as d. with ( )② . it’s necessary english chinese in english study. a. to b. with c. to d. into 【2011 四川广元】— why are most children under too much pressure
— because their parents always compare them ___ others. a. with b. by c. to 37. doctors say too much pressure is not good for a child’s development. 医生说太多的压力不利于孩子们的发展。 【解析 1】be good for 对......有好处 【拓展】good ( best) adj. 好的 → goodness n 好处；善行 ；美德 be good for 对….有益处（反） be bad for 对…有害处 be good at +n/doing=do well in +n/doing 擅长于做某事 be good to sb. =be kind to =be friendly to sb.对某人友好 【记】the boy is good ______me .he is good ______english , and he tells me oral practice is good ______improve spoken english. 【新疆中考】i think drinking milk is good ____ our health. a. for b. to c. with d. at23【湖北咸宁】 — i think drinking milk every morning is good ____ our health. — yes, i agree _____ you. a. to b. to c. with d. with 【山东临沂】english is my favorite subjiect , and i am good ___ it. a. for b. to c. at d. of 【解析 2】development 发展 【2012 江苏泰州】good habits are good for the ___________(develop) of us teenagers. 【2012 江苏盐城】 the ____________(develop) of science has changed our world a lot. 38.dr. alice green says all these activities can cause a lot of stress for children. 爱丽丝. 格林医生说所有的这些活动可能给孩子们带来很多压力。 【解析】 cause v. 造成，使发生 (1) cause sb. to do sth 使某人做某事 (2) cause sb. for sb. 给某人添麻烦 ( ( )① she always ___ trouble ___ people. a. to b. for c. to d. for )② every year driving after drinking wine ____ a lot of trafficaccidents. a. happens b. provides c. causes 【拓展】 cause, reason, excuse 辨析 ⑴ cause n.原因，指引起某种结果的“原因”，后接介词 of. the cause of the accident was the fact that he was driving too fast. 事故的原因是他开车开的太快。 ⑵ reason n.理由，原因，指决定做某事或采取某项行动的理由。 the reason he was driving so fast was that he didn’t want to miss an important meeting.他开车如此快的原 因是他不想错过一个重要的会议。 ⑶ excuse n.辩解，借口，指对某种行为所做的解释，可以是真的，也可以是托词。 he made a good excuse for his driving.他为自己开快车找了一个堂皇的借口。 ( ) what ___ the flowers to die a. made b. had c. caused d .get ( ) do you often ___ trouble ____ your parents a. into b. for c. for d. to 39. .in my opinion, it is important for children/ parents to ... 我认为， 对于孩子们/父母来说， ......是重要的。 【解析】in one’s opinion 以某人的观点； 在某人看来 40. perhaps children/ parents should / could ......或许孩子们/父母应该/ 可能....... 【解析】perhaps 也许；可能 【拓展】perhaps，probably，possibly，maybe 辨析 ⑴ perhaps 意为“也许，可能”，一般指比较小的可能性。 perhaps i will see him the day after tomorrow, but i am not sure. 也许我后天去看他，不过我不能确定。 ⑵ probably“很可能，大概”，其可能性最大，表示一种几乎完全肯定的意思。 he will probably refuse the offer.他很可能会拒绝这份提议。 ⑶ possibly 意为“可能，或许，也许”，可能性较大。24i’ll see you today, or possibly tomorrow.我今天要见你，不过也可能是明天。 ⑷ maybe“或许，大概”，主要用于非正式场合，常用在口语中，语气比 perhaps 轻。 maybe you put the letter in your basket. 或许你把信放在你的篮子里了。 41. it’s crazy. 这是疯狂的。 【解析】crazy. adj. 不理智的；疯狂的 (在句中作定语、表语、宾语补足语) be crazy about 对……着迷；热衷于…… i’m crazy about football. 42.