高中英语短语、语法、词汇大全分享，英语学习不在难（五）高中英语短语、语法、词汇大全分享，英语学习不在难（五）呈占趣字百家号情态动词第四章情态动词（一）情态动词表示说话人对动作或状态的各种观点和态度，如需要、猜测、意愿或怀疑等。情态动词有词义，但不完全，是所谓的“辅助性”动词，在句中不能单独充当谓语。一、 情态动词的特征和形式A.情态动词的各种形式见下表：情态动词maymightcancouldmusthave toought towillwouldshallshouldneeddareused to否定式may notmight notcannotcan notcould notmust notdo not have toought not towill notwould notshall notshould notneed notdare notused not todid not use to简略否定式mayn't（老式英语，现在不常见）mightn'tcan'tcouldn'tmustn'tdon't have tooughtn't to（否定句中to可省略）won'twouldn'tshan't（只用于英国英语）shouldn'tneedn'tdaren'tusedn't todidn't use toB．情态动词除ought to, used to等外，后面只接不带to的不定式。1．情态动词+doYou shouldn't be so careless.你不该这样粗心大意。Jessica told him yesterday she might not go on the trip.杰西卡昨天告诉他，她可能不去旅行了。Difficulties can and must be overcome.困难能够而且必须克服。2．情态动词+be doingShe must be listening to pop music.她肯定在听流行音乐。You should be reviewing your lessons.你应该在复习功课。My mother maymight be cooking now.我妈妈可能正在做饭。3．情态动词+have doneThey might have visited the Great Wall.他们可能参观过长城了。He must have got up very early to catch the train.他一定起得很早去赶火车了。You ought to have come earlier.你本该早一点儿来。4．情态动词+be doneThis word can also be used as a verb.这个词也可以用作动词。Something must be done to stop pollution.必须采取措施来制止污染。The work ought to have been finished long ago.这工作早就该完成了。C.情态动词第三人称单数一般现在时没有词形变化。You ought to wear a raincoat.你应该穿件雨衣。She ought to wear a raincoat.她应该穿件雨衣。Plants must have oxygen in order to live.为了存活植物必须有氧气。A plant must have oxygen in order to live.为了存活植物必须有氧气。D.情态动词的时态并不是区分时间的主要标志。在一些场合中，情态动词的现在式和过去式都可以表示现在时间、过去时间或将来时间。I'm afraid it might rain tonight.我看今晚可能要下雨。Could I borrow your thermos我可以借用你的暖水瓶吗？It's a nice day today. We could go for a walk.今天天气不错，我们可以出去散散步。E.情态动词是互相排斥的，一般不允许两个意义相近的情态动词连用。【误】Soldiers must have to obey orders.【正】Soldiers have to obey orders.军人必须服从命令。【正】Soldiers must obey orders.军人必须服从命令。【误】Can I be able to borrow two books at a time【正】Can I borrow two books at a time我能一次借两本书吗？【正】Will I be able to borrow two books at a time我能一次借两本书吗？一、 情态动词的意义和用法A. may和might1．表示请求、许可，常译为“可以”。在口语中可用can, could代替may，但在正式场合用may。表示允许时，也可用might代替，might不表示过去时，而是表示口气比较婉转。You may take this seat if you like.如果你喜欢可以坐这个位置。MayCan Could Might I have a talk with you我可以和你谈谈吗？--- MayMight I come into the room to see my mother我可以进房间看我母亲吗？--- No, you mustn't. She needs to have a good rest.不，你不能进。她需要好好休息。提示：May I ...问句常见的肯定回答和否定回答。肯定回答Yes, please.Certainly.Yes, of course.Sure.Go ahead, please.否定回答No, you can't.（最常见）No, you mustn't.（具有强烈禁止的意思）Please don't. You'd better not.I don't think you can.I'm sorry it's not allowed.2．表示推测，可译为“可能，也许”。Your math teacher maymight be in his office. 你们的数学老师可能在办公室里。（一般情况下，might表示的可能性很小）The light isn't on. It maymight be broken.那盏灯没有亮，它可能坏了。There may might be some ink left in the bottle.瓶子里也许还剩点儿墨水。注意：用may表示推测一般不用于疑问句，在疑问句中通常用can来代替。Can he be at home他可能在家吗？--- Can it be true这可能是真的吗？--- It may be, or may not be.可能是，也可能不是。3．用在目的状语从句中，构成谓语。He wants to take a taxi so that he may get there in time.他想坐出租车，这样他就能及时到达那里。I arrived at the airport earlier in order that I might meet him.我早早地就到了机场为了能接到他。4．有时可以用于祈使句表示祝愿。May you succeed.祝你成功May you be happy.祝你快乐。May that day come soon.希望这一天早日到来。B. can和could1．表示能力，可译为“能，会”。I can swim.我会游泳。Emily can dance well and her mother could dance well when she was young.艾米丽舞跳得很好，她妈妈年轻时舞跳得也很好。The cinema can seat 1,000 people.这电影院能容纳1，000人。I could not read such an easy book when I was 7 years old.我七岁时连如此简单的书我也看不懂。2．表示允许、许可，常用在口语中。could比can语气上要客气。--- Could I use your dictionary我可以用一下你的字典吗？---Yes, go ahead.可以，用吧。（或Yes, you can.但不能说Yes, you could.）Could Can you tell me how to get to the zoo劳驾，你能告诉我怎么去动物园吗？He asked me whether he could take the book out of the reading room.他问我可不可以把书带出阅览室。3．表示推测，可用于肯定句（can罕见）、否定句和疑问句，但更常见于疑问句或否定句。在此种用法中can和could没有时态的区别，只是表示可能性的大小，can表示推测的可能性比could大。Can he be ill at home他会是生病在家吗？Can the story be true这个故事会是真的吗？He cannot be at home.他不可能在家。You mustn't smoke while you are walking around in the woods. You could start a fire.在林子里走时一定不要吸烟，那样可能会引起火灾。4．表示惊异、怀疑、不相信等态度，主要用于否定句和疑问句中。How can you be so careless你怎么这么粗心？Where can could they have gone他们会去了哪里？He can'tcouldn't be over sixty.他不可能超过60岁。5．Could可以用在虚拟条件句中。If I could fly, I should be very happy.如果我能飞，我会很高兴。If you had followed my advice, you could have finished it.如果你当时听我的，你早就做完了。If you had tried harder, you could have passed your exam.如果你再努力些，你就能通过考试了。６．can与be able to的区别①can表示“能力”时，和be able to相当，许多场合都可以互相替换。但当叙述过去经过一番努力才能完成的事情或前面有特殊说明，表示你有能力时，只能用be able to。【正】Can you speak any foreign languages你会说外语吗？【正】Are you able to speak any foreign languages你会说外语吗？【误】The fire spread the building quickly but everybody could escape.【正】The fire spread the building quickly but everybody was able to escape.大火迅速蔓延到整幢大楼，但大家都逃了出来。【正】The fire spread the building quickly but everybody managed to escape.大火迅速蔓延到整幢大楼，但大家都想法逃了出来。②be able to比can有更多形式。No one could answer the question.没人能回答这个问题。（这里could可用was able to代替）When he grows up, he will be able to support his family.他长大后就能养家了。Frank is ill. He hasn't been able to go to school for one week.弗兰克病了，已经一周没去上学了。I'm sorry for not being able to help you in time.对不起，不能及时帮你的忙。③could经常和动词see, hear, smell, taste, feel, remember, understand等连用。When we went into the house, we could smell something burning.当我们走进屋子时，我们闻到什么东西烧焦了。（不用was able to）She spoke in a very low voice, but I could understand what she said.虽然她讲话的声音很低，但我还是明白了她说的话。④在谈论说话时发生的动作，用can，不用be able to。【误】Look! I'm able to swim.【正】Look! I can swim.看，我会游泳了！C．must和have to1．must表示有做某一动作的必要或义务，强调主观看法，可译为“必须，应该”。Everyone must obey the rule.人人都必须遵守制度。We must do everything step by step.我们必须逐步做每件事。Teachers must be patient enough with their students.老师必须对学生有足够的耐心。2．have to表示因客观需要促使主语不得不做某事。You can't turn right here. You have to turn left.你不能在这里右拐，你必须左拐。My eyesight is very poor. I have to wear glasses for reading.我的视力很差，看书时不得不戴眼镜。You have to pass a test before you can get a driving licence.你在取得驾照之前必须先通过考试。提示：在口语中，我们可以使用have got to来代替have to.I've got to work on Sunday.我不得不星期天工作。When has Ann got to go安必须什么时候走？3．must与have to的比较。must与have to在表示“必须”这个意思时意义相近，但在用法上有所区别。①must含有说话者的强烈决意（表示主观的看法），have to则表示外力环境或习惯使然（即表示客观的必要，作“不得不”解）。I must study hard.我必须努力学习。（发自内心的决定）I have to study hard.我不得不努力学习。（外界因素逼迫）You must stay for supper.你必须留下来吃晚饭。（because I want you to）You have to stay for supper.你得留下来吃晚饭。（because there is nowhere else to go）②must只有一种形式，而have to可有多种时态。They had to put off the sports meet due to the bad weather.由于坏天气，他们不得不推迟运动会。These last two days he has had to take a rest at home.这两天他必须一直在家休息。③must的否定式和have to的否定式的意思完全不同。You must keep it a secret. You mustn't tell anyone.你必须保密，你不可以告诉任何人。（mustn't表示“禁止”）You don't have to tell me the secret.你不必告诉我这个秘密。（don't have to意思是“没有必要”= don't need to）4．must用于表示推测，它的肯定程度比may, might, could大得多，一般只用于肯定句。①must do (这里的do通常是状态动词或系动词)，表示对现在状态的推测。He must be very lazy for his desk is very untidy.他肯定很懒，因为他的课桌很不整洁。Carol must get very bored with her job. She does the same thing every day.卡罗尔肯定对她的工作厌烦了，她每天都做同样的事。②must be doing表示对现在动作或状态的推测。Put on more clothes. You must be feeling cold with only a shirt on.多穿点儿衣服，你只穿一件衬衣，肯定觉得冷。③must have done表示对过去的动作或状态的推测。The ground is wet. It must have rained last night.地面是湿的，昨晚肯定下雨了。I didn't hear the phone. I must have been asleep.我没听见电话铃响，我一定是睡着了。提示：must表示推测只用于肯定句，否定句和疑问句要用can, could来代替must。He's just had his lunch. He can't be hungry already.他刚吃过午饭，不会饿的。They have just arrived here. They can't know many people.他们刚到这里，不可能认识很多人。Leslie walked past me without speaking. He can'tcouldn't have seen me.莱斯利从我身边走过而没打招呼，他肯定没看见我。5．must可用来表示根据逻辑推理必然要发生的事，可译为“必然会，总是会”。We all must die.我们都会死。Truth must be out.真相必然会大白的。Winter must be followed by spring.冬天到了，春天还会远吗？6．must有时可用来表示“偏偏”的意思。Why must it rain today为什么偏偏在今天下雨？When I was taking a nap, a student must knock at the door.正当我午睡时，偏偏一个学生在这个时候来敲门。D．will和would1.will和would可用于第二人称疑问句，表示请求和建议等。would比will委婉客气。Will you have some tea你喝点茶，好吗？Will you share your happiness with us你可以把你的欢乐与我们共享吗？Would you pass this book to the student in the last row请你把这本书传给最后一排的学生好吗？必背：WillWould you ...表示请求和建议的答复。肯定回答Yes, please.是的，请。Certainly.当然可以。Sure.当然了。All right.好啊！否定回答I'm sorry. I can't.对不起，不行。No, thank you.不，不行。No, I won't.不，不行。2．will和would可表示意志、愿望和决心，用于各种人称陈述句。I will do anything for you.我愿为你做任何事。I will never tell you the secret.我永远不会告诉你这个秘密。None is so blind as those who won't see.不愿看的人眼睛最瞎。They would not let him in because he was poorly dressed.他们不让他进去因为他衣着破旧。3．will和would可表示某种倾向或习惯性动作。will表示现在的习惯动作，would表示过去的习惯动作。He will surf the Internet every night.他每天晚上都在上网。The boy will sit there hour after hour looking at the traffic go by.那男孩常常坐在那儿好几个钟头，看着车辆行人通过。He would be nervous when he met strangers.遇见陌生人时他总是很紧张。In class he would ask some silly questions, and his classmates would laugh at him.课上，他总是问一些蠢问题，他的同学们总是嘲笑他。4．will可表示固执坚持，这时will不可使用'll的简略形式。用于非人称主语时，表示物体的固有性质和倾向。I will take the job, and no one can stop me.我就要这个工作，没有人可阻止我。He won't do what he's told.他就是不愿按所吩咐的去做。The window won't open.窗子打不开。This glass will not crack under heavy pressure.这种玻璃在重压下也不会破碎。5．will表示将来时间时，不可用于条件状语从句，但will表示意愿或决心时，可用于条件状语从句。If you will read the book, I'll lend it to you.如果你愿意读这本书，我会把它借给你。If you will give up smoking, your health will improve.如果你愿意把烟戒掉的话，你的健康状况就会好转。6．will和would可表示推论或猜测。The patient took the sleeping pills an hour ago. He will be asleep now.病人一小时前吃的安眠药，现在应该睡着了。It would be about ten when he left home.他大约在十点钟离开的家。I thought he would have told you about it.我认为他已告知你此事。It would be raining when she went home.她回家时可能正在下雨。比较：Would you like ...表示邀请Do you like ...表示习惯——Do you like going go the cinema你喜欢看电影吗？——Yes,I go to the cinema a lot.是的，我经常去看电影。——Would you like to go to the cinema tonight今天晚上去看电影好吗？——Yes,I'd love to.非常乐意。E．shall和should1．shall①表示征询意见或请求指示，用于一、三人称疑问句。Shall I carry it for you我来帮你搬它，好吗？Shall we sing a song我们唱一支歌，好吗？Shall they wait outside让他们在外面等吗？Shall the waiter bring meals to your room要服务员把饭送到你房间去吗？提示：Shall I open the window我打开窗子好吗？Will you open the window你打开窗子好吗？Shall he open the window他打开窗子好吗？②表示说话人的意愿，有“命令、允诺、警告、决心”等意思，用于第二、三人称陈述句中。You shall do as I say.按我说的做。（命令）He shall be sorry for it one day, I tell you.我告诉你，总有一天他会后悔的。（警告）You shall fall behind in your exam if you keep playing.如果你一直玩，你就会在考试中落后。Nothing shall stop us from carrying out the plan.什么也阻止不了我们执行这项计划。（决心）He shall have the book when I finish reading.我看完这本书就给他看。（允诺）I shall do my homework after reading this story book.读完这本故事书后我就做作业。2．should①表示义务，意为“应该”（某件事宜于做），用于各种人称。Children should obey their parents.儿童应该服从他们的父母。One shouldn't be selfish.人千万别自私。Customers who get bad service should complain, shouldn't they没有得到满意服务的顾客应该抱怨，不是吗？②常与what, how, why等词连用，表示意外、惊讶等情绪。How should I know我怎么会知道呢Why should I fear我为什么会害怕？What should she do but cry for help除了呼救外，她还能干什么？I don't know why you should think I did it.我真不知道你凭什么认为这件事是我干的。③表示对过去、现在或将来情况的某种推测，可译为“可能、照说应该”。It should be fine tomorrow.明天可能天是晴天。He should be taking a bath now.他可能在洗澡。It's nearly seven o'clock. Jack should be here at any moment.已经快七点了，杰克随时都可能到这儿。The film should be very good as it is starring first-class actors.这部新电影是一流演员主演的，估计拍得很好。④表示对现在或以前的动作的责怪、批评（应做的事却没做）。The boys shouldn't be playing football. They should be at school.这些男孩子不应该在踢足球，他们应该在上课。You shouldn't have entered the teachers' office without permission.没有允许你们不应该进老师办公室。F．ought to1．表示义务，意为“应该”（因责任、义务而该做），口气比should稍重。We ought to defend our country.我们应当保卫我们的国家。（每一个公民应尽的义务）You ought to respect your parents.你应当尊敬你的父母。Oughtn't we to do everything possible to stop pollution难道我们不应当尽可能地制止污染吗？2．表示推测，暗含很大的可能，可译为“应该是，会是”。Prices ought to come down soon.价格可能会很快下跌。Han Mei ought to know his telephone number.韩梅该知道他的电话号码。There' it ought to be a fine day tomorrow.今天有晚霞，明天应该是个好天。3．ought to和should一样，表示对现在或以前应做的事却没做的责怪、批评。You ought to be washing your clothes. Why are you playing Ping-Pong你应该在洗衣服（可是你没洗）。为什么你在打乒乓球？You ought to have handed in the exercise last week.你上周就应当交练习。（可你没交，含责备的意思。）He ought to have asked me before he took my bike.他在用我自行车之前应该和我讲一声。4．ought to与should的比较。ought to和should的含义较近，但不完全相同。ought to表示“应该”，是从“义务”或“按理推断”的角度来讲的。should则是从说话人的个人看法这一角度来讲的。You are her mother. You ought to look after her.你是她的母亲，你应当照管她。（是道义上的责任，不能和should互换。）We should encourage him for we are his classmates.我们应该鼓励他，我们是他的同班同学啊！提示：表示“义务”时，我们在口语中可以用had better或be supposed to来代替should和ought to。If you are not well, you had better ask Alice to go instead.如果你不舒服，你最好叫艾丽丝代替你去。I'm supposed to be there at 8 o'clock.我应该八点到那里。G．used to1．used to表示过去的习惯或过去某时期的状况，但现在已不存在。He used to drink tea but now he drinks coffee.他过去总是喝茶但现在他喝咖啡了。（强调现在不喝茶了）I know where there used to be a river here.我知道这儿以前哪里有条河。（现在没有河了）When I was a child I didn't use to like tomatoes.我小时候不喜欢吃西红柿。He is not what he used to be.他已不是原来的他了。Where did you use to live before you came here来此之前你住在什么地方？2．would和used to的用法区别。①used to表示过去与现在或过去某时与后来的情况有不同，强调“现已无此习惯了”，而would只表示过去的情况，与现在无关。When he was young, he would smoke a lot.他年轻时总是吸许多烟。（不含有和现在比较，现在他也许还在抽，也许不抽了。）He used to live in the country, but now he lives in the city.他过去住在乡下，现在住在城里。②used to可表示过去的习惯动作或状态，而would只表示过去的习惯动作。Kate used to be very thin.以前凯特非常瘦。There used to be a building at the street corner, but it has been pulled down.街道拐角处过去有座楼房，现在拆了。（不用would）③used to可泛指过去的习惯动作或状态，而would表示过去的习惯动作时，往往要带有一个特定的时间状语。【误】We would play hide-and-seek in the fields.【正】We used to play hide-and-seek in the fields.我们过去常在田野里玩捉迷藏。【正】Whenever we were in the country, we would play hide-and-seek in the fields.每当我们在乡下，我们都在田野里玩捉迷藏。H．daredare既可用作情态动词，也可用作行为动词，指勇气和胆量上的可能，可译为“敢”。1．情态动词dare①dare作为情态动词时主要用于疑问句和否定句，一般不用于肯定句中。I dare not daren't walk through the forest at night.我不敢在黑夜穿过森林。--- Dare you walk through the forest at night你敢在黑夜穿过森林吗？--- Yes, I dare.是的，我敢。--- No, I daren't.不，我不敢。He dare not drive too fast on the rainy day.下雨天他不敢开得太快。He dared not do it last year.去年他不敢做这事。（dare的过去时为dared）②可以用于表示怀疑的名词性从句中。I wonder how he dare say such things.我真奇怪他怎么竟敢说出这样的话。We don't know whether he dare climb the mountain.我们不知道他是否敢爬那座山。③可以用于条件状语从句中。If the enemy dare enter the village, we'll fight against them to the end.如果敌人敢进入村里，我们就和他们战斗到底。If you dare cheat in your exam, I will give you some punishment.如果你们敢在考试中作弊，我就惩罚你们。2．行为动词dare①dare可以作为行为动词，多用于肯定句中，但也可用在疑问句和否定句中He will dare any danger.他敢面对任何危险。He dared me to jump over the stream.他激我跳过小溪。Did anyone dare to admit it有人敢于承认吗？I have never dared (to) go back to take a look.我再也不敢返回去看一眼了。（否定句中to可省略）②和其他行为动词一样，dare在句子中要随着主语的人称和数发生变化。He doesn't dare to walk at night.他不敢走夜路。（作行为动词）He daren't walk at night.他不敢走夜路。（作情态动词）Does he dare to walk at night他敢走夜路吗？（作行为动词）Dare he walk at night他敢走夜路吗？（作情态动词）He didn't dare to walk at night fifteen years ago.15年前他不敢走夜路。（作行为动词）He daren't walk (=dared not walk) at night fifteen years ago.15年前他不敢走夜路。（作情态动词）Will you dare to do the same experiment tomorrow明天你敢做同样的实验吗？（作行为动词）Dare you do the same experiment tomorrow？明天你敢做同样的实验吗？（作情态动词）必背：英语口语中dare的几个常用结构：●I dare say...我想,大概,可能,或许……I dare say things will improve.我想情况会好转的。●How dare you ...你怎么敢……？How dare you ask me such a question你怎么敢问我这样的问题？●I dare you ...我谅你也不敢……I dare you to tell your parents!我谅你也不敢告诉你父母！I．need1．情态动词needneed和dare一样，作为情态动词时，主要用于否定句和疑问句，一般不用于肯定句中（在肯定句中常被must, have to, ought to, should等情态动词取代）。作为情态动词，它的词形只有need一种形式。You needn't return the book now. You can keep it till next week if you like.　你现在不必还书，如果愿意，你可以下周还。（needn't = don't have to）Need I hand in my homework now我现在就要交家庭作业吗？--- Need he finish the article next week他要下个星期完成这篇文章吗？--- Yes, he must.是的，他必须完成。--- No, he needn't.不，他不需要。（= he doesn't have to）2．行为动词needneed和dare一样，也可以作行为动词，可用于肯定句、否定句和疑问句中。行为动词need有人称和数的变化。Plant needs water.植物需要水。My shirt needs a button.我的衬衫需要一枚钮扣。My car needs repairing.我的车该修理了。He has grown up. We don't need to worry about him.他已经长大了，我们不必为他担心。You don't need to buy so many things for the picnic.你不必为这次野餐买这么多东西。Patience is needed for that job.干那工作，需要耐心。提示：Need作为情态动态时，不要用于肯定句中。【误】She need do her homework by herself. (need作为情态动词时，不用于肯定句中)【正】She needs to do her homework by herself.她该独立完成家庭作业。第四章情态动词（二）一、 情态动词+动词完成式“情态动词+have done”是情态动词的一个十分重要的结构，这种结构有两个主要的用法。表示对过去发生的动作或状态的推测或估计may might have done表示“大概已经”通常用于肯定句和否定句。might有时可用于疑问句。can could have done表示“可能已经”通常用于疑问句和否定句。could有时可用于肯定句。must have done表示“一定已经”只用于肯定句，具有较大的可能性should have done表示“该”,可能性较小表示对过去发生的动作的遗憾或责备might have done表示“本可以通常用于肯定句could have done表示“本可以通常用于肯定句。should have done表示“应该可用于肯定句、否定句和疑问句。ought to have done表示“应该”同should have done。needn't have done表示“本没有必要”只用于否定句。A．may /might /have done1．表示对过去事实不大肯定的推测，常译为“可能已经”。They might have taken a later train.也许他们乘坐的是晚一点儿的火车。He seems to know the city quite well. He may have been there before.他似乎对那个城市很熟悉，他以前可能去过那儿。2．表示“本来应该或可以做但没有做某事”，含有轻微的责备口吻或遗憾。You might have given him more help, though you were busy.你本来应该给他更多的帮助，虽然你很忙。The proposal might have been refused.这个建议本该拒绝的。B．cancould have done1．表示对过去事实的推测，常用于否定句和疑问句。He can't couldn't have watched TV yesterday for he knew they would have an exam.昨天他不可能看电视，因为他知道快要考试了。I don't know why she didn't call me yesterday. Can (Could) she have forgotten my telephone number我不知道昨天她为什么没给我打电话，难道她会把我的电话号码忘了吗？He didn't come to school yesterday. Can he have been ill他昨天没来学校，难道他生病了？2．could可表示对过去能做而未做的事感到惋惜、遗憾，可译成“本来是可以……的”。Why didn't Sophie apply for the job She could have got it.为什么索菲不申请这项工作？她本来是能得到的。Why did you stay at a hotel when you went to New York You could have stayed with Barbara. 你到纽约时为什么住宾馆？你完全可以和芭芭拉住在一起的。Given more time, we could have done the work better.如果给我们更多的时间，我们完全可以把这项工作干得更好。C．must have done1．表示对过去事实有把握的推测，具有较大的可能性。只用于肯定句中，否定句和疑问句用cancould have done。His watch must have stopped.他的表肯定停了。--- I rang your flat yesterday. A man answered but I didn't recognize the voice.昨天我给你家打电话，一位男士接了电话，但我没听出来是谁的声音。--- Oh, it must have been my brother Peter. 哦，那一定是我哥哥彼得。2．用于虚拟语气中时，表示与过去事实相反。You must have caught the bus if you had got up earlier. 如果你早一点儿起床的话，你准能赶上那一班公共汽车了。（事实上没有赶上公共汽车）He must have won the game if he had been careful enough.如果他足够细心的话，他准能赢得比赛。.D．needn't have done用于对过去的责备，表示“没有必要做某事，可是做了”。The airport is close to us. You needn't have hurried there early.机场离这儿很近，你没必要早早地赶到那里。（可是你早早地到那儿了）He is still young. You needn't have sent him such an expensive present.他还小，你没必要送他这么昂贵的礼物。注意：如表示“过去不必做也没有做”之意，需用didn't need to do。It is not cold today. I didn't need to take the thick sweaters out.今天天气不冷，我没有必要把厚毛衣拿出来。（实际上也没拿）E．shouldought to have done1．表示对过去动作的责备或批评。You should have gone over your lessons. (In fact you didn't go over your lessons.)你们应把功课复习好的。（可事实上你们没有。）You shouldn't have watched TV last night. (In fact you watched TV last night.)你们昨天晚上本不该看电视。（可你们看了。）You oughtn't to have entered the teachers' office without permission.没有经过允许，你们本不该进老师的办公室。You oughtn't to have gone to the deserted place alone. 你不该独自去那荒凉之地。2．表示期待或推测。If the flight was on time, you should ought to have arrived in Shanghai early this morning.如果航班准点的话，你今早就能到上海了。The building should ought to have been completed by the end of the week.这幢建筑物本周末前应该能完工。F．would have done表示与过去事实相反的假设或结果。I would have been happy to see him, but I didn't have time.我会很高兴和他见面的，但我没时间见他。If your father had still been alive, he would have felt very proud of you.你父亲如果还健在的话，他会为你骄傲的。动词不定式第五章动词不定式（一）动词不定式是动词的一种非谓语形式，在句中不能单独作谓语。动词不定式具有动词的性质，它可以有自己的宾语和状语，从而构成动词不定式短语。它还可以有形式的变化，即一般式、进行式、完成式和被动式。同时，动词不定式也具有非动词的性质，相当于一个名词、形容词或副词，可以在句中担任主语、宾语、宾语补足语、表语、定语和状语。一、动词不定式的特征和种类动词不定式是由不定式符号to+动词原形构成，在某些情况下to也可省略。A．不定式的一般式不定式的一般式表示的动作通常与主要谓语的动作同时或几乎同时发生，或是在它之后发生。He appears to be very happy.他看起来好像很高兴。（同时发生）To catch the train, we'd better hurry to the station by taxi.为了赶上火车，我们最好赶紧乘出租车去车站。（to catch the train发生在hurry to the station之后）B．不定式的进行式不定式的进行式表示正在进行的或与谓语动词同时发生的动作。It happened to be raining when I got there.我到达那里的时候，天碰巧在下雨。I'm glad to be traveling with you.我很高兴和你一起旅游。C．不定式的完成式不定式的完成式表示的动作在谓语表示的动作之前发生。I'm sorry to have lost your key.我很抱歉把你的钥匙弄丢了。I meant to have finished my work last night, but I didn't feel very well.我本来想昨晚完成工作的，但是我感觉身体不舒服。It has been an honor for me to have been invited to your country.对我来说，被邀请来你们国家是一件很荣幸的事情。D．不定式的完成进行式不定式的完成进行式表示的动作在谓语之前发生并且一直进行着。He was said to have been living in London for twenty years.据说他在伦敦一直住了20年。I'm sorry to have been interrupting you.很抱歉，我一直打扰你。比较：不定式的时态意义。He is said to be studying abroad.据说他正在国外读书。（不定式的进行式表示动作正在进行）He is said to have studied abroad.据说他在国外学习过。（不定式的完成式表示动作已经结束）E．不定式的被动形式当不定式逻辑上的主语是这个不定式表示的动作的承受者时，不定式一般要用被动形式。不定式的被动形式根据其与谓语动作发生的先后关系，有一般式和完成时两种。1．一般式to be doneThese are the books to be given out to the students.这些是要发给学生的书。He asked to be sent to the place where he was most needed.他要求被派往最需要他的地方。2．完成式to have been doneThe novel is said to have been translated into many languages.据说这部小说已被译成多种语言。He appeared to have been questioned for many times.看起来他已经被询问过很多次了。F.不定式的否定形式不定式的否定形式由not或never加不定式构成。We decided not to go out because of the bad weather.由于天气不好，我们决定不出去。Never to have made any mistake is impossible.从不犯错是不可能的。注意：谓语动词的否定和不定式的否定不同的意义I did not promise to wake him up.我没有答应叫醒他。I promised not to wake him up.我答应了不叫醒他。一、动词不定式的用法动词不定式除了不能单独作谓语外，几乎能担任句子中所有的句子成分。A．动词不定式作主语不定式具有名词的特征，可在句子中充当主语。1．不定式短语在句首作主语To know oneself is difficult.人贵有自知之明。To say is one thing and to do is another.说是一回事，做又是另一回事。To love and to be loved is the greatest happiness one can get.爱与被爱是一个人能获得的最大幸福。2．用it作形式主语在很多情况下，人们通常用it作为形式上的主语，而把不定式移到谓语之后，使句子结构显得平稳一些。It's rude to turn your back to your teacher and refuse to answer.背对着老师，拒绝回答问题是不礼貌的。It is impossible to learn a foreign language without making painstaking effort.想不下苦功就能学会外语是不可能的。It seemed a pity to have wasted so much time.浪费了这么多时间，真是遗憾。注意：当主语和表语都是不定式时，不能用形式主语代替动词不定式。To respect others is to be respected.尊重别人就是尊重自己。To become a slave is to give up one's freedom.做奴隶就等于放弃自由。B．动词不定式作表语不定式作表语可以说明主语的具体内容或表示目的。His wish is to become an astronaut. 他的愿望是成为一名宇航员。What he hoped was to be admitted into the university.他希望能被大学录取。To live is to do something worthwhile.活着就是要做一些有价值的事情。注意：有些作表语的不定式，在结构上是主动的，但在意义上却是被动的。She is to blame.她应该受到责备。The house is to let.此房出租。The result is not long to see.结果不久就会看到。C．动词不定式作宾语不定式可以充当部分及物动词的宾语，也可以充当but和except等介词的宾语以及形容词的宾语。1．作动词的宾语①不定式可以充当部分及物动词的宾语。Father likes to listen to music in silence. 父亲喜欢静静地听音乐。He prefers to be starved to death rather than beg. 他宁愿饿死也不愿乞讨。I never thought to meet you here.我没想到在这里遇见你。必背：可接不定式作宾语的动词有：afford负担得起agree同意aim以……为目标ask要求attempt尝试begin开始care喜爱choose决定continue继续decide决定desire要求determine决心expect期待fail不能forget忘记hate不愿hope希望ntend打算manage设法mean打算offer表示愿意plan计划prefer宁愿pretend假装promise答应refuse拒绝remember记起try努力want想要wish希望②在feel, find, make, think, consider等动词后，如果宾语带有宾语补足语时，人们常常用it作形式宾语，而把真实宾语放在宾语补足语之后。I found it possible to work out the problem without a computer.我发现有可能不用计算机而解出这道题目。She made it a rule to get up at five.她养成了五点起床的习惯。I feel it a great honor to be invited to speak at the meeting before so many students.我觉得被邀请在会上面对这么多学生发言是一件很光荣的事情。③在表示“希望、打算”等动词（如hope, expect, intend, mean, want等）的过去式后，可接动词不定式的完成式来表示没有实现的动作。I intended to have called on you, but was prevented from doing so.我原想来拜访你的，但没来成。I expected to have met him here last night.我以为昨天晚上能在这里见到他。（但没做到）We meant to have stayed there a week.我们原打算在那儿呆一个星期的。I wanted to have dropped her a line, but forgot to do so.我原想写一封信给她，但忘记了。提示：表示“原打算、原以为”还可以用这类动词的过去完成时来表达。I had intended to call on you.我原想来拜访你的。I had expected to meet him here last night.我原以为昨天晚上能在这里见到他的。We had meant to stay there a week.我们原打算在那儿呆一个星期的。2．作介词的宾语不定式可以作介词but和except的宾语。The teacher made no comments except to tell him to work hard.老师除了叫他努力学习外，未做任何评价。He had no choice but to sit there as usual. 他没有什么选择，只好像往常一样坐在那儿。There is nothing we can do but wait patiently. 我们只能耐心等待。3．作形容词的宾语不定式作形容词的宾语有两种句型，一个是句子的主语是不定式的逻辑主语，另一个是句子的主语是不定式的逻辑宾语。①句子的主语是不定式的逻辑主语。这类形容词有able, afraid, angry, anxious, careful, clever, content, cruel, determined, disappointed, eager, foolish, fortunate, frightened, happy, impatient, glad, lucky, naughty, prepared, proud, ready, slow, shocked, sorry, surprised, willing等。I am sorry to say that he is going from bad to worse. 很遗憾，他的情况每况愈下She was not content to live a quiet life in a small town.她不满足在一个小镇里过默默无闻的生活。John was happy to be given the job.约翰得到这份工作很高兴。②句子的主语是不定式的逻辑宾语。这类形容词有easy, hard, cheap, expensive, dangerous, difficult, funny, fit, impossible, interesting, nice, pleasant, simple, strange, useful等。This problem is easy to solve.这个问题很容易解决。The water is not fit to drink.这水不适于饮用。She is hard to get along with.她这个人很难相处。注意：在这种结构中，如果不定式是不及物动词，则必须加上结构或含义所需的介词。The river is dangerous to swim in.在这条河里游泳很危险。A spring mattress is comfortable to sleep on.席梦思床垫睡上去很舒服。D．动词不定式作宾语补足语不定式可以在“主语+谓语+宾语+宾语补足语”句型中充当宾语补足语。在这一句型中，宾语是动词不定式的逻辑主语。1．在表示感觉的动词后作宾语补足语，并且不定式都不带to。这类动词有：see, hear, feel, watch, notice, observe, look at, listen to等。I heard them sing yesterday.昨天我听见他们唱歌了。Did you see him go out你看见他出去了吗？I felt something crawl up my leg.我感到有什么东西爬到我腿上了。注意：转为被动语态时，原不带to的不定式要变成带to的不定式。notice和watch没有被动语态。We saw the car stop.n The car was seen to stop.我们看见这辆车停了下来。n2．在使役动词后作宾语补足语，不定式不带to。这类动词有：make, let, have等。转为被动语态时，其后通常都用带to的不定式（have没有被动语态）。有些动词跟不定式作宾语补足语时省去了to，这些动词有：一感二听三让四观看。一感：feel 二听：hear,listen to 三让：let,have,make 四观看：observe,see,watch.,look atWhat would you have me do你要我做什么？She made him give up smoking.她让他戒了烟。Let him do whatever he wishes to do.他想干什么就让他干吧。Though he had often made his little sister cry, today he was made to cry by his little sister. 虽然经常是他弄哭小妹妹，但今天他却被小妹妹弄哭了。3．在表示心理状态的动词后作宾语补足语。这类动词有：consider, think, believe, discover, find, imagine, judge, suppose, prove等。这类动词后的不定式通常是“to be+形容词或名词”结构，think, consider, find后的to be常可省略。We consider him (to be) a good teacher.我们认为他是一个好老师。He proved that theory (to be) very important. 他证明那个理论是很重要的。I thought her (to be) nice and honest the first time I met her.我第一次见到她的时候就认为她人很好，很诚实。4．在表示情感状态的动词后作宾语补足语。这类动词有：love, like, prefer, hate, want, wish, expect等。I'd prefer you to leave him alone.我希望你不要打扰他。I don't want there to be any trouble.我不想有任何麻烦。5．动词advise, allow, ask, beg, command, tell, invite, force, oblige, get, help, encourage, persuade, permit, remind, request, order, warn, cause等后面，多接不定式短语作宾语补足语。We don't allow such things to happen again. 我们不容许这种事情再发生。Most of the parents agree to forbid their children to smoke.大多数父母都同意禁止自己的孩子抽烟。She asked me to answer the phone in her absence.她请我在她不在的时候接电话。Please remind me to leave her this note.请提醒我留给她这张纸条。She requested him to go with her.她邀请他一同去。注意：hope, demand, suggest等动词后面不能接不定式作宾语补足语。【误】I hope you to give me a hand.【正】I hope you can give me a hand.我希望你能帮我一把。【正】I wish you to give me a hand.我希望你能帮我一把。【误】He demanded me to be present at the meeting.【正】He demanded that we should be present at the meeting.他要求我们出席会议。【正】He required us to be present at the meeting.他要求我们出席会议。【误】Mr Li suggested her not to go there alone.【正】Mr Li suggested that she should not go there alone.李先生建议她不要独自去那里。6．动词不定式也可作一些短语动词的宾语补足语。I'm waiting for James to arrive.我正等着詹姆斯的到来。He's arranged for a car to pick them up at the station.他已安排了一辆汽车去车站接他们。The UN has called on both sides to observe the ceasefire.联合国号召交战双方遵守停火协定。必背：这些带介词的短语动词有：call on号召arrange for 安排ong for盼望wait for等待depend on 依靠rely on 指望E．动词不定式作定语不定式作定语通常放在其修饰的名词或代词之后，和被修饰的名词或代词之间是主谓关系、动宾关系、同位关系和修饰关系。1．主谓关系The future to greet us will be bright.我们的未来会十分美好的。He is always the first person to come and the last one to leave. 他总是第一个来最后一个离开。The next train to arrive was from New York.下一列到站的火车是从纽约开来的。2．动宾关系On Sundays, he always has a lot of letters to write.星期天，他总是有许多信要写The teacher left us a lot of problems to solve.老师给我们留了许多道题要解答。He can find no one to make friends with.他找不到可交朋友的人。注意：由于动词不定式与其修饰的词之间往往有动宾关系，因此，如果该不定式是不及物动词，其后应有必要的介词。She has a child to take care of.她有一个孩子要照看。There is nothing to worry about. 没什么可担心的。He has no friend to depend on.他没有可依靠的朋友。I've got a lot of things to see to this morning. 今天上午我有许多事情要处理。3．同位关系He broke his promise to write to his parents regularly.他没有遵守诺言定期给他父母亲写信。We students should have the courage to face any difficulty.我们学生应该有勇气面对任何困难。I have no wish to quarrel with you.我不想和你吵架。4．修饰关系Now it is time to begin our class.现在是上课的时间了。I need somewhere to take a nap.我需要一个地方打个盹。Is that the way to open the can那就是打开罐头的方法吗？F．动词不定式作状语不定式作状语可以表示行为的目的、结果、原因、条件等。1．表示目的I'm saving up to buy a computer.我在存钱买电脑。To save the child, he laid down his life.为了救那个孩子，他献出了生命。注意：有时为了强调或突出这种目的，也可以用in order (not) to do,和so as (not) to do结构（so as to do不可以置于句首）。He shouted and waved in order to be noticed.为了吸引注意，他又嚷嚷又挥手。I'll write down his telephone number so as not to forget it.我要把他的电话号码记下来，以防忘记。2．表示结果He got to the station only to find the train had gone.他赶到车站，发现火车已经开走了。What have I said to make you so angry我说了什么话使你气成这样？After the meeting, they parted, never to see each other again.散会后，他们分手了，从此再也没有见面。必背：不定式表示结果常见于下列句型。1）so ... as to doWould you be so kind as to lend me your bicycle把你的自行车借给我好吗？2）such ... as to doWe are not such fools as to believe him.我们还没蠢到竟会相信他。3）enough to doHe didn't run fast enough to catch the train. 他跑得不够快,没赶上火车。4）only to doHe lifted a rock only to drop it on his own feet.他搬起石头砸自己的脚。5）too ... to doHis eyesight is too poor to read such small letters.她的视力太差了，不能看这么小的字。注意：too...to...结构中的形容词如果是eager, pleased, happy, ready等，动词不定式不表示结果，也没有否定的意思。The boy was too eager to get a geography book.那个男孩非常急切地想要得到一本地理书。He is too anxious to know the examination results.他很急切地想知道考试结果。3．表示原因I was a fool not to listen to you at that time. 我当时不听你的话，真是傻瓜。She wept to find him in such a difficult situation.看到他处于这么困难的情形，她哭了。4．表示条件A man would be blind not to see that.一个人如果看不到这点，那他就是瞎子。How can you catch the train to start so late这么晚才动身，你怎么能赶上火车？第五章 动词不定式（二）一、动词不定式的几种常见结构A．不定式的复合结构动词不定式的逻辑主语（即不定式动作的执行者）通常是句子的主语或宾语。如果不定式的逻辑主语不是句子的主语，此时一般用“for +名词（代词）+不定式”来构成不定式的复合结构，这种复合结构在句中可以做主语、宾语、表语、状语、定语。This box is too heavy for the little boy to carry. 这个箱子让这个小男孩来搬太重了。That's for you to decide.那个由你来决定。He stood aside for me to pass.他站到一边让我通过。I have some books for you to read.我有几本书送给你读。B．be +不定式结构“be +不定式”结构可以表示将来发生的动作，常有以下两种情况：1．表示命令和指示The room is to be locked.这房间要上锁。You are not to stand here.你不能站在这里。2．表示计划或安排We are to begin the work next month.我们安排下一个月开始这项工作。What's to be done next下一步该怎么办？C．疑问词+不定式结构疑问词who, what, which, when, where, how, why后加动词不定式构成不定式短语，它在句中可作主语、宾语和表语。I don't know whether to go to the meeting or not.我不知道要不要去开会。The problem was how to get rid of the waste thrown by the passengers.问题是如何处理乘客们丢弃的垃圾。When to visit the Palace Museum has not been decided yet.何时参观故宫博物院还没有决定。D．withwithout +名词+不定式结构“withwithout +名词+不定式”结构在句子中通常起状语的作用。With so much work to do, I shall not be able to go to the cinema with you.有这么多工作要做，我不能和你去看电影了。With him to stay in the house, I feel quite safe.有他住在家里，我感到十分安全。Without anything to eat, he died of hunger.由于没有东西吃，他饿死了。E．It is +形容词+ forof sb + to do结构在“It is +形容词+ of sb +不定式”结构中，形容词往往表示人物的性格和特征，如kind, silly, good, unwise, clever, wrong, right, foolish, stupid, careless, rude, impolite, bold, thoughtful, honest, bad, sensible, naughty等。在“It is +形容词+for sb +不定式”结构中，形容词通常表示事物的性质，如important, possible, impossible, necessary, difficult, hard, reasonable等。It's kind of you to think so much of us. 难为你这么为我们着想。(= You are kind to think so much of us.)How careless it is of him to break such a valuable vase!他真不小心，把如此贵重的花瓶打破了。It is easy for me to see through his trick.我很容易看穿他的鬼把戏。(=For me to see through his trick is easy.)It is hard for him to get rid of his bad habits.他很难改掉自己的坏习惯。比较：It is good lf you to help me with my English. 你真好，帮助我学英语。（强调you的特征＝You are good to help me.）It is good for you to give up smoking. 戒烟对你有好处。（强调的是give up smoking这一行为＝Fof you to give up smoking is good.）F．分裂不定式动词不定式to do通常是不拆开的，但偶尔也可在不定式符号to和动词原形之间插入一个副词，构成分裂不定式。He was too ill to completely carry out that program.他病得太重，不能完成那个项目。He has made up his mind to once more try this method. 他已经下定决心再试试这个方法。G．用作独立成分的不定式有一些不定式短语可以作状语修饰整个句子，也可被称为插入语。To be honest, we are not sure to find the girl in the forest.说老实话，我们不能确保在森林里能找到那个女孩。To be frank, I don't agree with what you said. 坦率地说，我不同意你说的话。必背：用作独立成分的不定式to tell you the truth说老实话to be frank 坦率地说to begin with首先to be brief简言之to make a long story short长话短说to be exact精确地说to say nothing of姑且不说to conclude总而言之to be sure诚然，固然to do him justice说句对他公道的话so to speak可以这么说H．用主动式表示被动含义的不定式动词不定式在句中究竟用主动还是被动，有时比较复杂，主要有下面几种情况：1．不定式做后置定语，和被修饰的名词或代词构成逻辑上的动宾关系，但又和该句主语构成逻辑上的主谓关系时。Do you have anything to say on this question针对这个问题你有什么要说的吗？He is a pleasant person to work with.他是一个与其合作起来令人感到愉快的人。2．不定式作形容词的宾语，和句子主语构成逻辑上的动宾关系时。The book is difficult to understand.这本书很难理解。The chair is comfortable to sit on.这把椅子坐起来很舒服。3．There be结构中，当说话人考虑必须有人去完成某件事时。There is nothing to worry about.没什么可担心的。There is nothing to fear.没有什么可害怕的。比较：There is a lot of work to do.有许多事情要做。（表示某人必须做这工作）There is a lot of work to be done.有许多事情要做。（强调有许多事情必须做）She has two letters to type.她有两封信要打。（自己打）She has two letters to be typed.她有两封信要打。（别人打）I．表示虚拟语气的不定式完成式。I hoped to have met him at the railway station, but he didn't turn up.我本希望在火车站接到他，但他未露面。We would love to have gone to the match, but the tickets were all sold out.我们原想去看这场比赛的，但票已售完了。The plane was to have taken off at 9, but something went wrong.飞机原计划九点起飞，但出现了一些故障。J．用于感叹句。不定式可用于感叹句，含有惊异、不满、惋惜或赞美等感情色彩。To think that he should do this!想想，他竟然干出这等事！（表示惊讶）Oh, God, to see her dance !哦，天哪，看看她的舞蹈！（表示赞美）To think that all the money has been wasted.想想，所有的钱都被浪费掉了！（表示不满）一、关于不定式符号的几个问题A．不带to的不定式1．在口语中，动词原形come和go后可接不带to的不定式。Go tell her.去告诉她吧。Come have a glass.来喝一杯。2．在why引起的一些问句中，疑问词直接跟动词原形或not+动词原形。Why make so much noise 为什么发出这么大的噪音？Why not join us 为什么不加入我们？3．在had better, had best, would rather, would rather...than, would sooner, would sooner...than, cannot but, cannot choose but, cannot help but等结构后直接跟动词原形或not +动词原形。You'd better listen to your teacher's opinion. 你最好听一听老师的意见。We had best call for the doctor at once.我们最好马上就请医生来。She can't do anything but ask silly questions.她一直在问一些愚蠢的问题。Rather than ride on a crowded bus, he always prefers to ride a bicycle.他宁愿骑自行车，也不愿挤公共汽车。He cannot but move to another street, because his building has to be pulled down soon.他不得不搬到另一条街上去，因为他住的大楼很快就要被推倒。We cannot help but admire his courage. 我们情不自禁地钦佩他的勇气。4．如不定式前有行为动词do，那么在表语从句中的不定式和介词except或but之后的不定式可不带to。The only thing I could do was go home.我能做的唯一一件事就是回家。They could do nothing but wait for the doctor to come.他们只能等待医生的到来。5．在两个动词不定式并列使用时，为了避免重复，后面的不定式符号to可省略。The little girl hardly knew whether to laugh or cry.这小姑娘不知道是哭好还是笑好。Can you help me to call him and ask him to attend the meeting at 200 p.m.你能不能帮我打电话给他，叫他下午两点来开会？6．在help之后，既可用带to的不定式也可用不带to的不定式。Can I help (to) carry the box for you我帮你搬箱子，好吗？7．在一些固定搭配中用不带to的不定式。He let go the rope.他松开了绳子。I hear say there will be an earthquake soon.我听说不久就要有一次地震。She made believe she was innocent.她假装清白。8．在感官动词see, hear, watch, feel, notice以及使役动词make, let, have等后作宾语补足语的动词不定式不带to。She watched the children cross the street.她看着孩子们穿过了马路。They made the boy apologize to his friend for being so rude.他们让那男孩因他的粗鲁而向他的朋友道歉。Don't forget to have him come earlier.别忘了让他早点儿来。B．不定式符号的单独使用为了避免重复上文中出现过的动词，可以用不定式符号to来代替上文中出现过的不定式结构。1．在助动词或情态动词之后，如be going to, used to, have to, ought to, be able to, be about to等。She must go but you don't have to. 她必须走，但你没有必要。---Do you think I ought to go to see my doctor 你认为我应该去看医生吗？---Yes, I think you ought to. 是的，我想你应该去。2．在want, decide, like, love, hope, wish, mean, refuse, try等动词之后。You may go with them if you hope to. 如果你希望的话，你可以和他们一起去。---Did you go to see the Great Wall 你游览长城了吗？---I wanted to, but I was too busy. 我本来想去的，但我太忙了。3．在做宾语补足语的ask, tell, order, advise, persuade, warn, wish, permit, allow, forbid等动词之后。Don't do anything unless your father tells you to. 除非你父亲叫你去做，不然不要做任何事情。---May I use your car 我可以用你的汽车吗？---No, I forbid you to. 不，我禁止你使用。4．在对话的答语中的happy, glad, eager, anxious, willing, ready, pleased, afraid等形容词之后。---Will you lend me a hand 你能帮我一个忙吗？---I'm willing to, but I can't now. 我很愿意，但现在不行。---Would you please come to my birthday party tomorrow明天下午来参加我的生日聚会好吗？---I'll be glad to.我很乐意。提示：如果动词不定式是to be或to have，则一般不省。--- Did you finish the work你的工作完成了吗？--- No, but I hoped to have.没有，但我希望已经完成了。C．介词to和不定式符号toto既可以是不定式符号，后接动词原形；to也可以是介词，后接名词或动词的-ing形式。英语中有很多常用短语带有to，我们要正确判断to是不定式符号还是介词，千万不可混淆。1．不定式符号toHe made it a rule to read English aloud for half an hour every morning.他坚持每天早晨朗读半小时英语。These young lads are longing to go to watch the football match.这几个小伙子极想去看足球赛。必背：常见的带不定式符号to的短语be supposed to do应该做某事be determined to do决心要做某事fail to do未能做某事go all out to do全力以赴做某事have the nerve to do有胆量做某事have a great mind to do很想做某事make a point to do坚持做某事make up one's mind to do决定做某事take the trouble to do不辞辛苦地做某事prepare oneself to do有思想准备做某事2．介词toIf you stick to the truth, you will have nothing to fear.如果你坚持真理，就没有什么可害怕的。You must get used to getting up early.你必须习惯早起。Isn't it time you got down to marking those papers难道还没到你定下心来阅卷的时间吗？必背：常见的带介词to的短语be used to习惯be equal to胜任be given to沉溺于be opposed to反对be related to与……有关devote oneself to献身于get down to着手做give rise to引起lead to导致look forward to盼望object to反对pay attention to注意put one's mind to全神贯注于stick to坚持本文仅代表作者观点，不代表百度立场。系作者授权百家号发表，未经许可不得转载。呈占趣字百家号最近更新：简介:专业的趣字分析，我们来聊聊作者最新文章相关文章