修改情态动词.doc

情态动词情态动词主要用以表明说话者对某一行为的态度和观点。包括揣测、判断、需要、可能等意思。情态动词的特点:1.情态动词本身有一定词义，但不能单独作谓语，必须和句子的主要动词（实义动词）一起构成谓语。I can do it. 我能做这件事。2.情态动词一般没有人称和数的变化，在各种人称后形式相同。只有have to除外，第三人称单数作主语时，用has to。I (you), He (she), We (you, they) can do it.We have to leave. 我们不得不离开。He (she) has to leave. 他（她）不得不离开。3.情态动词后接动词原形。We must study hard. 我们必须努力学习。You had better go home. 你最好回家。4.有些情态动词有过去式，但must, ought to, had better, would rather没有，只有一种形式。一般式canmayshallwilldareneedhave(has)tobe able to过去式couldmightshouldwoulddaredneededhad towas/were able to一、情态动词的基本用法：I、can的主要用法1.表示能力(indicating ability) I can run very fast.2.表示获得的知识或技能（indicating acquired knowledge or skill） They can speak French.3.与感官动词连用(used with verbs of perception) I can hear music.4.表示许可或要求(indicating permission and requests) Can I read your newspapers? Can you feed the cat?5.表示可能性（indicating possibility） He cant have slept through all that noise.7.用以表示疑惑或怀疑（used to express bewilderment or incredulity） Can she be serious?8.用以描述特有的行为或情形（used to describe typical behavior or state） It can be quite windy on the hills 山上的风就是那么大。9.用以提出建议（used to make suggestions） We can eat in a restaurant, if you like.II. may的主要用法1. 表示允许、许可（indicating permission）You may come, if you wish.2. 表示可能（indicating possibility）This coat may be Peters.3. 表示目的（indicating purpose）I will write today so that he may know when to meet us.4. 用以表示愿望和希望（used to express wishes and hopes）May you both be very happy.III. must的主要用法1. 表示必要（indicating obligation）I must go to the bank to get some money2. 表示劝告或建议（indicating advice or recommendation） I must ask you not to do that again. 我的劝你不要再做那种事情了。3. 做出逻辑的推断（drawing a logical conclusion） You must be hungry after your long walk.4. 表示坚持，“非得；偏偏”（indicating insistence）You simply must read this book -its so funny.你一定得看看这本书-太有趣了。IV. would的主要用法1. 用以表示一设想事情的结果（used to describe the consequence of an imagined event）If you went to see him, he would be delighted.2. 与have + P.P 连用，表示假设的过去的动作或者事情（used with have + a past participle to describe a hypothetical action or event in the past ）If I had seen that advertisement, I would have applied for the job.3. 用以表示假想的现在的动作或者事情（used to describe a hypothetical action or event in the present）She would be a fool to accept the roses.4. 用以提出客气的请求（used in making polite requests）Would you pay me in cash, please?5. 与like, love, hate, prefer, be glad/happy等连用，表达较合意愿的做法（used with like, love, hate, prefer, be happy/glad, etc to express preference）Id love coffee.6. 用在so that，in order that之后，表达目的（used after so that, in order that to express purpose）She burned the letters so that her husband would never read them.V. shall的主要用法1. 表示预言（indicating future predictions）We shant know the results until next week.2. 表示意愿或决心（与二、三人称连用）（indicating will or determination）You shall have a new dress for your birthday.3. 表示询问或征求别人的意见看法（与一、三人称连用）（indicating offers or suggestions）Lets look at it again, shall we?Shall he stay here for the night?4. 表示说话人的允诺，警告，命令，威胁，法律规定等，用于二、三人称（indicating orders or instructions）If you work well ,you shall be well paid He says he wont come, but I say he shall. If you go there again, you shall lose what youve got. Candidates shall remain in their seats until all the papers have been collected.VII. will的主要用法1. 用来表示对未来事情的预料（indicating future predictions）How long will you be staying in Paris?2. 用以表示对目前事情的预料（indicating present predictions）They will be home by this time.3. 用以表示愿意或者不愿意（indicating willingness or unwillingness）We wont lend you any more money.4. 用以表示请求（indicating requests）Will you post this letter for me ,please?5. 用于发出命令或者指示（giving an order）Will you be quiet!6. 用于叙述真理时（describing general truths）Oil will float on water.7. 用于叙述目前或过去的习惯时（describing habits in the present or past）She will listen to music, alone in her room, for hours.(她独自一人在屋里听音乐，一听就是好几个小时)He would spend hours on the telephone.(他以前一打电话就是老半天)VIII. should的主要用法1. 用以表示义务或责任（indicating obligation）We shouldnt drink and drive.2. 用以表示劝告或推荐（indicating advice or recommendation）He should stop smoking.3. 用以表达假定的结果（used to describe the consequence of an imagined event）We should arrive before dark.4. 用于if 和in case之后或将主语与动词倒置，表示某事不太可能发生（虚拟语气）（used after if and in case, or with subject and verb reversed, to suggest that an event is unlikely to happen）If you should change your mind, do let me know.Should anyone phone, please tell them Im busy.5. 用于so that 或者in order that之后，表示动机或目的（used after so that/in order that to express purpose）He put the cases in the car in order that he should be able to make an early start.6. 表示不感兴趣、难以置信、惊讶等（to express lack of interest, disbelief, etc）Why should he think that?That he should speak to you like that is quite astonishing.IX.ought to 的主要用法1. 表示责任或义务（indicating obligation） They oughtnt let their dog run on the road.2. 表示劝告或推荐（indicating advice or recommendation） You ought to improve your English before going to work abroad.You ought to see her new film.(你应该看看他新拍的电影。)3做出推测性结论（drawing a tentative conclusion） Look at the sky- it ought to be a fine afternoon.Xhave to 的主要用法构成否定或者疑问句时，通常在前面要加do,在口语中常说成have got to1. 表示责任或义务（indicating obligation） He has to pass the examination before he can start work.2. 用以表示劝告或建议（indicating advice or recommendation） You simply have to get a new job.1. 得出合乎逻辑的结论(drawing a logical conclusion)There have to be a solution.XI. might的主要用法1. 用以表示许可（indicating permission）Might I make a suggestion ?2. 表示可能（indicating possibility）He might get here in time, but I cant be sure.3. 用于询问情况（asking for information）How long might that lecture take?4. 用于委婉的请求或者吁请（used to make polite requests or appeals）I think you might at least offer to help.(我认为你至少应该主动的帮帮忙吧！)XII. could 的主要用法1. 表示允准（indicating permission）Could I borrow your bicycle?2. 表示请求（indicating requests）Could you type one more letter before you go?3. 表示结果（indicating result）Im so unhappy I could weep.(我难过得要哭)4. 表示可能性（indicating possibility）You could be right, I suppose.5. 表示建议（indicating suggestions）We could write a letter to the headmaster.XIIIdare 和need的主要用法这两词既可作实义动词用，又可作情态动词用。作为情态动词，两者都只能用于疑问句，否定句和条件句。 need 作实义动词时后面的不定式必须带to，而dare作实义动词用时，后面的to 时常可以被省略。句型时态情态动词dare实义动词 dare肯定句现在时dare/dares to doneed/needs to do过去时dared to doneeded to do否定句现在时darent/dare not doneednt/need not dodo/does not dare (to) dodo/does not need todo过去时dared not doneed not have donedid not dare (to) dodid not need to do疑问句现在时Dare he do?Need he do?Do you/Does he dare (to) do?Do you/Does he need to do?过去时Dared he do?Need he do?Did he dare (to) do?Did he need to do?几点说明：关于dare1. dare用作情态动词尤其用于否定或者疑问句中，在if或whether之后，或者与hardly, never, no one, nobody连用，意为“竟敢”“胆敢”。（used asp in negative sentences and questions, after if/whether, or with hardly, never, no one, nobody）I wonder whether he dare stand up in public.2. 习语how dare you, he, she等，用以表示对他人举动的的愤慨（used to express indignation at the action of others）How dare you say that I copied your notes?(你怎么敢说我抄了你的笔记？) 3 习语I dare say, 意为“我相信”“可能”（I accept sth as a true or possible fact） I dare say you are British.关于needneed用作情态动词时，仅用于否定句及疑问句，或用于if及whether之后或与hardly，scarcely，no one等连用1. 表示必要（indicating obligation）You neednt finish that work today.He wondered whether they need send a deposit.(他不知道是否他们得交定金。)Nobody need be afraid of catching the disease.(谁都不用害怕能得上这种病。)2. 与have + PP连用，表示曾做的事无必要（used with have + a past participle to indicate that the action in the past were or may have been unnecessary）You neednt have hurried.Need they have sold the farm?(他们那时非得把农场卖掉吗？)3. need 的被动含义：need，want，require，worth（形容词）后面接doing，可以表示被动：sth. need(s ) doing= sth. need(s) to be done. was/were able to的主要用法1. 表过去的能力That boy wasnt able to walk when he was two years old.2. 设法做成(=managed to/succeeded in) He was able to flee Europe before the war broke out.= He managed to flee Europe before the war broke out.二、情态动词表示猜测的用法一定，肯定must一定不，不可能cant/couldnt可能肯定句will/would/should/can/could/ may /might否定句may /might not疑问句can /couldmodal v. +do sth.现在发生的动作be doing正在发生的动作have done过去发生的动作不同的“肯定”程度可按下列层次排列：He is at home.（事实）He must be at home.（非常肯定的推测）He could be at home.（很可能）He ought to be at home.（很可能）He may be at home.（仅仅可能而已）He might be at home.（或许，非常不确定）He might not be at home.（也许不在家）He may not be at home.（比might可能）He couldnt be at home.（很可能不在家）He cant be at home.（一定不在家）He isnt at home. （事实）三用于虚拟语气的情态动词should/might/could/would/neednt/ought to. should have done 本应该做（而没做） should not have done 本不应该做（事实上做了） He shouldnt have said such a thing .他当时不应该说那种话。 We should have studied last night, but we went to the concert instead 这种句式也能用ought toneed not have done没有必要做某事I need not have got up so early . 我本来不必要那么早起床的（事实上早已起床）I need not have waited for the train for an hour. 我本来不必要等一个小时的火车。（事实上已经等了一个小时）3. could have done过去本来能够（实际上没能做） If you could have finished the task in time，you could have been promoted. 如果你当时能如期完成那任务的话，你可能已提升了（实际上没有被提升） I could have laughed to hear him talk like that.听他那样讲话，我差点笑出声来。4. might have done过去也许/有可能（实际上没有） If she had started a little earlier， she might have been in time for the train.如果她早点出发，她有可能及时赶上火车。(实际上没有早出发，便没有赶上火车) It might have been better to stop then.如果那时就停止的话，也许比较好。5 would have done 与过去事实相反的假设结果，“当时就会