module5情态动词.doc

情态动词一 语法特点：情态动词，在英文中主要用来表示说话人的看法、态度等。从用法上来说，它有这样几个特点：1）各个情态动词自身都有一定的词义。2）不能在句中独立担当谓语，也没有非谓语形式。3）情态动词在句中不受任何人称,数变化的影响。4) 情态动词后接的不定式（除ought外）都不带to ，即接动词原形。主要有：can , could ; may , might ; must ; ought to; need ; dare , dared ，另外，shall , will , should , would在一定的场合也可用作情态动词。二 情态动词的用法（一） can 的用法1 表能力 (1）cancould 表示能力；可能 (过去时用could), be able to可以用于各种时态。如： The boy _ play the piano very well when he was seven .(2) was were able to 和could 在表示能力时可以替换；当表示成功地做了某事时，只能用_相当于_或_ . 不能用_。He was able to flee Europe before the war broke out.= _=_(3) 助动词后只用be able toThey will _ tell you the news soon. 他很快就能告诉你消息了。(4) 情态动词后只用be able to 。They may _ do it .2 表示许可，允许，在疑问句中表示请求许可，在否定句中表示不许。此时代替更为正式的May .-_I come in ? You _smoke in non-smoking sections in public places , but you can in smoking-sections .The teacher said that we _ play foot ball on the playground .注意：could在表示提出请求时和推测时，不表示时态。 - Could I have the television on? - Yes, you _. ( -No, you _.（注意在回答中不可用could）)3表示推测或怀疑，会多用于_句和_句中。句子翻译：他会是谁呢？_他不可能正在等你。 _他不可能已独自去那里了。 _4. 强调客观可能性“可能” He is in poor health. _ 他身体不好，随时都可能会生病。_ 即使是专家也可能会出差错。（二） may 的用法 1表示允许或请求；口语中常可与can替换。 如：你现在可以走了。_2. 表示没有把握的推测；”或许，可能”表示一件事情或许会发生，只用在陈述句中。 如：他可能来，但我认为他不会来。_注意： might 表示推测时，不表示时态。只是可能性比may 小。He might be at home.3 may 放在句首，表示祝愿。(半倒装结构) 愿上帝保佑你！_4 成语： may/might as well do 意为不妨，最好。If that is the case , _.如果那样的话，你不妨试一下。 典型例题 Peter _come with us tonight, but he isnt very sure yet. A. mustB. may C. can D. will（三） 比较have to和must 1两词都是必须的意思，_表示客观的需要，_ 表示说话人主观上的看法，既主观上的必要。如：我弟弟病得很厉害，我只得半夜里把医生请来。(客观上需要做这件事)_他说他们必须努力工作。（主观上要做这件事） _比较：I must leave now .(主观) Im afraid youll have to leave now , its a rule of the hospital .（客观）2_有人称、数、时态的变化，而_只有一种形式。He had to look after his sister yesterday.3 在否定结构中： dont have to 表示_mustnt表示“_”你不一定要把此事告诉他。_你一定不要把这件事告诉他。 _4在回答带有must 的问句时，否定结构不用_, 而用_-Must I go home ?-Yes , _ / -No ,_5 must表示偏偏，偏要做，（指做令人不愉快的事情） The car must break down just when we were about to start off . Must you shout so loudly ?6 must表示推测 1) must用在_句子中表示较有把握的推测，意为_。2)must be 对_ 推测 must be doing对_ 推测 must have done 对_ 推测must have been doing对_ 推测1你辛苦干一整天，一定累了。（对现在情况的推测）_2他一定在办公室工作呢。_3我刚才没有听到电话，我想必是睡着了。_ 4-Why didnt you answer my phone call?-Well, I _,(sleep) so I didnt hear it. 5比较：He must be staying there._ He must stay there. _5) 否定推测用cant be / couldnt be cant be doing / couldnt be doingcant have done /couldnt have done（四）shall 用法1.表示命令、警告、强制、威胁，承诺，规定，宣判, 决心等。一般用于二、三人称。1) You shall have my answer tomorrow 2) .He shall be sorry for it one day , I tell you .3) .You shall do as I tell you .4). Nothing shall stop us from fighting against pollution2. 用于征求对方的意见和指示，用在一，三人称的疑问句中。1）Shall I turn on the light ? 2）Shall he come to see you ?注： Shall +第三人称主格+do sth =Do you want +第三人称宾格+to do sth .（五） should 用法Should不是一个单独意义的情态动词，它只是shall 的过去式。1 表示劝告，建议常作应该，应当之义，与ought to 有时可以互换，ought to更注意一些责任义务。 You should do it by yourself .2 表示按常理进行推测，预测其可能性，译为“应该，可能” He should be in his office now .3.should带感情色彩，常用在why , how 开头的疑问句中。Why should I invite him ? How should I know ？（六）will 1表示意志，意愿和决心，用于各种人称。 Ill do my best . I will never do that again. -Who can close the door ?-I will (Ill do it )2表示各种倾向, 习惯动作 或必然发生的动作。 Boys will be boys . 男孩毕竟是男孩。Fish will die out of water .3 will be /will have done表示一种揣想推测，用于二三人称。That will be the book you want.They will have arrived by now .他们大概已经到了。4 用于疑问句表示请求，邀请。（ would更委婉）Will you give me a piece of paper ?5 表示功能 ，意为“能，行” The door wont open. （七）would would 是will的过去式，would +v 构成过去将来时，除此之外，是单独的情态动词。1 表示过去时间的“意志，愿望和决心”I told him that I would go along with him .2 委婉提出请求，建议或看法，语气比will委婉，肯定答语用will .Would you help him ? Yes , I will .3 表示过去的习惯动作和过去的某种倾向。When he was a child he would (used to )play football .Would 和 used to 的区别：_ 主要用于今昔对比，表明过去如何，现在已不再如此了。_表示追忆往事，有感情色彩。（八） need 的用法1 need 的意思是“”需要，既是行为动词，又是情态动词。 作行为动词时，他具有一般动词的各种形式，（need needs needed needing） 作 情态动词，只有一种形式，没有人称和数的变化，后接动词原形，与not 连用时构need not的否定式，疑问句把need提前。情态动词不用在_句中，只用于_和_句中1) Need he work so late ? Yes, _ No , he _.2) You neednt walk that fast , _? 你不必走那么快，行吗？注意1: sth need doing = need to be done_（九） dare的用法1.作_动词时，主要用于疑问句，否定句及条件句中，陈述句中很少使用但（I dare say ）除外。没人称和数的变化，但有时态变化，过去时为dared. 否定式为darent .How dare you say Im unfair ?He dare not speak English before such a crowd , dare he ?2 作_动词时，有时态，人称和数的变化，肯定句中，dare to do，但在否定句和疑问句中，其后的to 可省可不省。I dare to swim across this river .He does not dare (to) answer Dont you dare (to )touch it ? （十） 情态动词+ have done情态动词+have done是历年高考的重点和难点之一，现将其用法总结归纳如下： 1 “must have done”表示对过去事情的肯定推测，译成“一定做过某事”，该结构只用于肯定句。 1)_last night, for the ground is wet. 昨晚一定下雨了，因为地面还是湿的。 2) _to speak to the servant. 你和仆人说话，一定是发疯了。 2. “cant have done”表示对过去事情的否定推测，译成“不可能做过某事”。 1). _, for I saw him in the library just now. 史密斯先生不可能去北京了，我刚才还在图书馆见过他。 2). _. She has gone home. 玛丽不可能偷你的钱，她回家去了。 3 “can have done”表示对过去行为的怀疑，用于疑问句，译成“可能做过吗？”。 1). There is no light in the room. _? 屋里没有灯，他们可能出去了吗？ 2). There is nowhere to find them. _? 到处找不到他们，他们可能到什么地方去呢？ 4. “could have done”是虚拟语气，表示对过去事情的假设，意思是本来能够做某事而没有做。 _, but he was too careless. 本来他能够通过考试，但是他太粗心。 5 “may have done”表示对发生过的事情的推测，意思是“可能已经”或“也许已经”，用于肯定句。 What has happened to George? 乔治发生了什么事？ I dont know. He _. 我不知道，他可能迷路了。 6. “might have done”表示对过去事情的推测，might与may意思相同，但可能性更小。多用于虚拟语气结构中。 1). He _, even though he was busy. 他本可以多给你一些帮助，即使他很忙。 2). She _, if you had given her more chances. 如果你多给她点机会，她可能已经取得更大的成绩。 7 “would have done”虚拟语气，表示对过去事情的假设，意思是“本来会做，本来想做”。 1)_, but you didnt ask me. 我本来会告诉你这个小男孩的故事，但是你没有问我。 2) Without your help, I _. 没有你的帮助，我是不会取得如此大的成绩。 8“should have done”意思是“本来应该做某事，而实际没做。” “shouldnt have done”表示本来不应该做某事，而实际做了。含有指责对方或自责的含意。 1). Tom, you are too lazy. The work _. 汤姆，你太懒惰了，这项工作本来应该昨天就做完的。 2) Look, Tom is crying. I _. 看，汤姆哭了，我本来不应该对他如此严厉。 9 “ought to have done”表示过去应该做而实际并没有做，译成“理应做”，往往表示遗憾。与“should have done”用法基本一样。 1)_ 我理应上星期日回家。 2)_ 你不应该帮助他那么多。 10 “need have done”表示本来需要做某事而没有做。“neednt have done”则表示“本来不需要做某事而做了”。 1)_only five people came. 我本来没有必要买这么多酒，只来了五个人。 2)He _. In that case, be wouldnt have missed the train. 他本来需要快点去车站，那样的话，他就不会误了火车。 情态动词巩固练习1. - _ I go out to play now, Mum? - No, you _. You should do your homework first.A. Must; mustnt B. Must; wouldnt C. May; neednt D. May; had better not2. _ you like to have a walk with us this evening?A. Did B. Would C. Should D. Can3. You _ be careful when you cross here - the traffic lights arent working.A. could B. might C. ought to D. may4. We were all waiting for you; you _ without leaving a message.A. mustnt leave B. neednt leave C. shouldnt have left D. couldnt have left5. It _ be she that told him about it; it _ be you, because only you and I know it.A. mustnt; must B. couldnt; must C. mustnt; might D. couldnt; might6. A hardworking man _ become a great scientist, but a great scientist _ be a hardworking man.A. cant; can B. may not; can C. cant; must D. may not; must7. You _ go right now if you want, but I think you _, because we have enough time.A. must; may not B. must; cant C. may; neednt D. may; mustnt8. - Why do you ask me to do the difficult work? - Because you _ do such a thing and nobody else is fit for it.A. would B. can C. should D. may9. You _ be tired; you have been working for so long a time, but he _ be tired; he has just begun to work.A. may not; must B. must; may not C. cant; must D. must; cant10. Its said that there are plenty of hotels in that town. There _ be any difficulty for you to find somewhere to stay.A. wouldnt B. mustnt C. shouldnt D. neednt11. Dont believe him. What he said _ be true.A. mustnt B. neednt C. shouldnt D. may not12. - Must I take a bus? - No, you _. You can walk there.A. must not B. may not C. dont have to D. had better not to13. - Do you think he will help me? - As far as I know, he is the last one to help others. He _ be prepared to give you a hand, though.A. can B. must C. might D. should14. You _ return the dictionary now. You can keep it till next week if you like.A. cant B. mustnt C. dont need D. dont have to15. The thief _in from the kitchen window as all the other windows and doors were closed.A. may climb B. must have climbed C. could climb D. should have climbed16. - We want someone to design the new art museum for us. - _ the young fellow have a try?A. May B. Shall C. Will D. Need17. - Must we do it now? - No, you _.A. wont B. neednt C. cant D. dont18. - I dont know why he is late. - Nor do I. He _ an accident.A. could have had B. should have had C. might have had D. must have had19. I got up early, but I _ so because I had no work to do that morning.A. mustnt have done B. shouldnt have done C. neednt have done D. cant have done20. - _ he use your bike？- Certainly. Here is the key.A. Shall B. Must C. Will D. Does21. You_ all those clothes! We have a washing machine to do that sort of thing.A. neednt have washed B. shouldnt have washedC. must not have washed D. can not have washed22. Johns score on the test is the highest in the class; he_ last night. A. should study B. should have studied C. must have studied D. must have to study23. The room is in a terrible mess; it _cleaned. A. cant have been B. shouldnt have been C. mustnt have been D. wouldnt have been24. Mary was not in her bedroom yesterday afternoon. She _ in her classroom. A. should have been B. must have been C. must be D. should be25. You_ to town to see the film yesterday. It will be on TV tonight. A. neednt go B. had better not go C. should not go D. neednt have gone26. We_ the letter yesterday, but it didnt arrive. A. must receive B. ought to receive C. must have received D. ought to have received27. Eve was late for class again. She _earlier. A. should get up B. must get up C. need to get up D. should have got up28. I am feeling sick. I_ so much chocolate. A. neednt have eaten B. couldnt have eaten C. mustnt have eaten D. shouldnt have eaten29.When I got to the cinema, the film had already started; I_ there earlier. A. ought to get B. ought to have got C. must have got D. must get30. The road was muddy. It_ last night. A. must rained B. must have rained C. must be rained D. could have rained31. You should bear in mind that he is not so strong as he_. A. was used to be B. used to be C. was used to D. use to32. We didnt see him at the exhibition yesterday. He _it.A. mustnt visit B. cant have visited C. should have gone to see D. may see 33. Mary _my letter, otherwise she wou