情态动词与虚拟语气

常考情态动词的用法1. can/could(1) 表能力(be able to)。(2) 表许可或客观条件允许。(3) 否定句和疑问句中表推测。(4) 肯定句中，表客观上、理论上的可能性。解释为“有时会”Whales _ not live on land.-Could I borrow your bike? -Yes, you _.There is no light in the room. She _ be at home now._ this be true?It is usually warm in my hometown in March，but it_ be rather cold sometimes.Dont play with the dog，Jack，for it_be dangerous at times.注意：(1) can never/ cant too + adj./adv. (adj./adv. enough) 解释为“越越好，无论也不为过”(2) was/were able to 和could 的区别was/were able to表示过去经过一番努力，终于能够完成某事。相当于managed to或succeeded in doing sth.。而could只表示过去的习惯能力。The fire spread through the hotel very quickly but everyone _ get out.I talked for a long time, and in the end I _ make her believe me.2. may(1) 表许可，请求can。(2) 表可能性，用于肯定句。might比may可能性小。may not意为“可能不”，表示一种不太确定的语气，比cant 的语气弱。(3) 表祝愿，祈求。_ I smoke here in the room?Is there an express to Beijing tonight?There _ be，but youd better call the booking office to make sure.-Is John coming by train? -He should, but he _. He likes driving his car._ you succeed！注意： (1) may/might as well (not) do /have done不妨，倒不如(2) may well do 很可能做(3) -May I look at your new computer? -Yes, you _. / No, you _.3. must(1) 表示必须，应该。(2) 表把握性很大的推测，用于肯定句。解释为“一定”(3) 表示“偏偏，偏要”，指发生了与说话人的愿望相反或令人不愉快的事情。(4) (表必然性)必定，必然。(5) must not表禁止，不允许。You _ do as you are told. He _ be very rich, for he often travels abroad.If you _ smoke，please go outside.The car _break down just when we were about to start off.All men _ die注意：must 和have tomust表示说话人主观认为的“必须”，而have/has to表示客观的需要，也可译为“不得不” 。have to 有时态和人称的变化，而must没有。 I really _ stop smoking.我真的该戒烟了。（我认为应该戒） I _ stop smoking.我得戒烟了。（可能医生的要求或身体的客观情况使我戒烟）4. shall(1) 用于主语为第一、三人称的疑问句中，表征求意见，请求指示。(2) 用于主语为第二、三人称的陈述句中， 表示说话人的命令、警告、允诺、威胁等；用于第三人称，指条文/约、合同、遗嘱等中的义务和规定。_ we begin our class?_ she go to the concert with us this evening?Dont worry. You _ get the answer this very afternoon. He _ be sorry one day. I tell you. According to the school rules，no student _ go out of the school after eleven oclock at night without the teachers permission. 5. should/ought to(1) 应当，应该(2) (表惊讶、遗憾)竟然；居然(只能用should)(3）表按常规有一定依据的推测，解释为“按理来说”。You _ help your mother with the housework. You cant imagine that a well-behaved gentleman _be so rude to a lady.The public transport in Beijing is very convenient，so there _ be any difficulty in traveling around the city.注意：should 有时和I连用，表委婉语气。You are mistaken, I should say. 要我说， 你搞错了。6. will /would(1) 表请求。would比will更委婉，客气。(2) 表意愿(3) 表倾向性(4) will表现在的习惯性动作，would表过去的习惯性动作。_ you please pass me some salt?If you _wait, I will go and ask if the manager can have the time to meet you.The car _ start.In those days, whenever I had difficulties, I _ go to Mr Shen for help.注意：would和used towould 单纯表示过去的习惯性动作，used to既表过去经常的动作，也表过去经常的状态，并强调过去的行为同现在的对比，含有“过去怎样，而现在却不这样了”。She isnt what she _ be.7. needneed既可作情态动词，也可作行为动词。（1）作为情态动词，没有人称和数的变化, 后接动词原形。通常用在疑问句、否定句、条件句中。(2) 作为行为动词, 有人称和数的变化，用于肯定句、否定句、疑问句中，构成否定句或疑问句时要用助动词do, does, did。_ he _ to go so soon?He _(not) to go.He _(not) go.注意：(1) need doing/ to be done The floor needs _(clean). (2) -Need we do it again? -Yes, you _./ No, you _.8. daredare既可作情态动词，也可作行为动词。（1）作为情态动词，没有人称和数的变化，后接动词原形。dare 可以有过去式dared。通常用在疑问句、否定句、条件句中。(2) 作为行为动词, 有人称和数的变化，后接to do。用于肯定句、否定句、疑问句中，构成否定句或疑问句时要用助动词do, does, did。用于疑问句、否定句，后面的to也可省略。 _ you ask him? She _(not) go out alone.She _(not) (to)ask her father.9. 情态动词对过去表推测 (1) cant/couldnt have done (2) Can/Could have done?(3) may/might have done （4）must have done10.情态动词表推测的反意问句 (1) He cant be at home, _?(2) His book must have been published last month, _?(3) He may have watered the plant yesterday, _? （4 He must have been told the news, _?填空练习：(1)I shall be glad if you _ help me.(2)_ you tell me something about yourself?(3)You _ not go to the dinner party if you dont finish your work this afternoon.(4)I _advise you not to do that.我倒是建议你别这样做。(5)-When can I come for the photos? I need them tomorrow afternoon.-They _ be ready by 12:00.(6)All men _ die.人必然会死的。(7)Its surprising / strange that he _ be so rude.(8)According to the rule, candidates (候选人)_remain in their seats until all the papers have been collected.(9)No one answered the phone. They _(go) home.(10)-How old are you, madam? -Well, if you _ know, Im twice my sons age.(11)Look, she is very sad now. You _( not tell) her the bad result.(12)The train _ leave at 10 p.m. and Ill make a call to make sure.(13)The fire spread through the hotel very quickly but everyone _ get out. (14)Look, his coat is still here, so he _have left.(15)Who _ the man at the gate be?(16)I promise you _ see her again before long.(17)This child is usually naughty, but he _ be quiet.(18)My dictionary is missing. Who _ have taken it away?(19)Although they_(可能未作出） any new discoveries, but they have done their best in the past ten years. (20)Its nearly seven oclock. Jack _ be here at any moment.虚拟语气虚拟语气就是表示说话人的愿望、假设或建议，而不表示客观存在的事实。虚拟语气通过谓语动词的特殊形式来表示。1、虚拟语气用于条件状语从句中以下表格是虚拟语气用于条件状语从句中时，主句和从句谓语动词的形式：条件状语从句主 句例 句与现在事实相反的假设动词用一般过去式（be动词用were）would/could/might/should +动词原形If I were a boy, I would join the army.If she had time, she would go with you.与过去事实相反的假设动词用had donewould/could/might/should + have + 过去分词If he had taken my advice, he would have succeeded in the competition.与将来事实相反的假设动词用一般过去式或should+ 动词原形或were to+ 动词原形would /could/might/should + 动词原形If it were to rain tomorrow, the football match would be put off.If you came tomorrow, we would have the meeting.If he should not come tomorrow, we would put off the meeting till next Monday.注意：（1）混合虚拟条件句。当条件状语从句表示的行为和主句表示的行为所发生的时间不一致时，动词的形式要根据它所表示的时间作相应调整。如： If you had asked him when you saw him last time, you would know what to do now.（2）if省略。如果省略if, 句子则可换成下列形式，即“were / had / should +主语”。如：Were I a boy, I would join the army.Had he taken my advice, he would have succeeded.Should he not come tomorrow, we would put off the meeting till next Monday.（3）含蓄虚拟条件句。有时虚拟条件句并没用if 从句表示出来，而是用otherwise, or, without, but, but for等表示。We didntknow his telephone number; otherwise/or we _(telephone) him.Without you help, I wouldnt have achieved so much.But for your help(=If it hadnt been for your help), I would not have succeeded.I would have bought the mobile phone, but I _(not have) enough money then.2、虚拟语气用于名词性从句（1）虚拟语气在宾语从句中的运用。“wish + 宾语从句”及“if only引导的感叹句”表示不能实现的愿望，译为“要是就好了”等。用过去时表对现在虚拟，用过去完成时表对过去虚拟，用 “would/could/might + 动词原形”表对将来虚拟。如：I wish it were spring all the year round.I wish I had known the answer. I wish I could fly like a bird.If only I were a bird. If only I had taken his advice. If only the rain would stop.在表示命令、建议、要求等的动词suggest、advise、recommend、propose、demand、require、insist、 request、command、order等后的宾语从句中，谓语动词用(should) + 动词原形。如：She suggested we (should) leave here at once.The doctor ordered she （should） be operated. would rather +宾语从句I would rather I were a bird.(与现在情况相反，动词用过去式(be用were)I would rather that you hadnt known it. (与过去情况相反，动词用had+过去分词)I would rather you came here tomorrow. (与将来情况相反，动词用过去式(be用were)注意：suggest表“建议”insist 表“坚持要求”时，其后的宾语从句用虚拟语气，但当suggest表“暗示，表明”，insist 表“坚持认为”时，其后的宾语从句用陈述语气。如；The man insisted that he _(not steal) the money and that he _(set) free.Your pale face suggests that you _(be) ill and I suggest you _(go) to the doctors at once.（2）虚拟语气在同位语从句和表语从句中的运用。作表示命令、建议、要求等的名词advice、order、demand、proposal、suggestion、request等的表语从句和同位语从句，从句中的谓语动词用“（should） + 动词原形”。如：His suggestion that we (should)go to Shanghai is wonderful.（3）虚拟语气在主语从句中的运用。在主语从句中，谓语动词的虚拟语气用“should + 动词原形”的结构，表示“应该”“竟然”。用于“It is + 形容词 (necessary, important, natural, desirable, advisable, surprising, unbelievable, strange, etc.) + that从句” 用于“It is + 名词 (a pity, a shame, no wonder, etc.) + that 从句”用于 “It is + 过去分词（desired，suggested, ordered, requested, proposed, etc.)+that从句”It is necessary that we should clean the room every day.It was a pity that you should be so careless.It is desired that she should finish her homework this afternoon.拓展：在动词expect, believe, think等动词的否定或疑问形式后的宾语从句中， should do/have done 表惊奇、怀疑、不满等。 They just couldnt believe that the stadium should be so big. 3、虚拟语气用于状语从句虚拟语气在as if/as though引导的状语从句中，用过去时表对现在虚拟，用过去完成时表对过去虚拟。如：She speaks English so fluently as if she were an American.He behaved as if nothing had happened.注意：as if /as though 也可用于陈述语气，表示谈论可能或真实的事情。如：It looks as if its going to rain.4、虚拟语气用于某些句型、短语中（1） “It is (high) time + that从句（从句的谓语动词用过去时或should+动词原形，should 不可省略）（2）would rather + 从句（从句的谓语动词用过去时表对现在或将来虚拟，用过去完成时表对过去虚拟） (3) would rather (not) have done （4）may/might as well (not) have done (5) would like to have done (6) in case从句（用should do） (7) had hoped/intended/meant to do = hoped/intended/meant to have done5、虚拟语气在口语交际中的回答 -Did you go to the museum? -No. I _(本来会去的), but I was too busy. 6种回答：would have, was to have, was going to, had meant to, meant to have, would like to have6、情态动词表虚拟的用法(1) could have done 本来可以做某事(2) might have done本应做某事（比should have done的语气委婉）(3) should (not) have done 本（不）应做某事ought (not) to have done (4) would rather (not) have done 宁愿（没有）做过某事(5) neednt have done 本来不必要做(而实际上做了) 区分 didnt need to do 过去没有必要做某事（而实际也没做）(6) would like to have done 本想做某事(7) may/might as well (not) have done 还不如（不）做了某事7、情态动词表推测的用法（见情态动词最后）填空练习：1.We all felt worried about you. You _（不应离开）without a word.2.I didnt tell him the date of the meeting, but I _.3.- My father made a call to Mr. Smith just now. -Oh, he _. Mr. Smith is coming here tomorrow.4.I went to see the film with Jack, but I _(宁愿没去).5.-Where did you stay when you were in New York?-I stayed in the hotel.-Oh, you _(stay) with Babara because she has a large house.6.-Did you manage to repair the machine last night ?-No, and the whole night was wasted.-Oh, you _ (turn) to my brother for help. He is quite an expert in it.巩固练习1. The boy_be really annoying at times，but after a while，youll get used to himA. must B. should Cshall D. can2. -Did you go to the fashion show last week？ -I_，but I was fully occupied the whole week A. must go B. must have gone C. would go D. would have gone3. She_well let out the secret，for she looked very upset when seeing me.A. can B. may C. must D. shall4. I cant thank you too much for your kindness because without your help I have won the first prize in the speech contestAcant Bshouldnt Cmight not Dcouldnt 5. I wonder why Tom is late again.Well，he _ his train, or maybe overslept.A. might missB. may have missed C. should missD. must have missed6. They didnt take measures in time, otherwise the explosions _some experts saidAwouldnt happen Bdidnt happenCwouldnt have happened Dmustnt have happened7. What do you mean, there are only ten tickets? There be twelve.A. must B. can C. will D. should8 more energy to my study instead of being crazy about Internet games, I would be sitting in a comfortable office now AIf I devoted BHad I devotedCWould I be devoted DShould I be devoted9. Have you checked the engine?Yes, I did twice; there _ be anything wrong with the car. A. wont B. mustntC. neednt D. shouldnt10. He _ the first place again, in which case, his mother will be more than happy. A. cant win B. would have won C. might win D. could have won 11.It was the drug，not the disease，that killed the boy.He would be still alive today if he _ that drug.A. not take B. shouldnt have taken C. didnt take D. hadnt taken12. Students _ remain in their seats until all the papers have been collected.A. mayB. shallC. needD. can13. We _ the work on time without your help.A. hadnt had finished B. didnt have finishedC. couldnt have finished D. cant have finished14What is a left-luggage office?It is a place where luggage be left for a certain period of time, especially at a bus or a train station.AcanBshouldCmustDwill15. Can I have something to eat, Mum? I feel hungry. You _ be hungry. Youve just had some bread and ham. A. maynt B. wont C. mustnt D. cant16. At a construction site in our city the workers have uncovered an ancient wall that_ to keep the enemy out of the city, but it requires further evidence.A. might have functioned B. would have functionedC. must have functioned D. should have functioned17. I am going to buy the overcoat if the shopowner lower the price.Amust Bshould CcouldDwill18.According to the school rules,no student go out of the school after eleven oclock.A.will B.must C.may D.shall19Im leaving now Its so lateBetter stay with meCall a taxi if you Awill Bmust C. would Dmay20.What do you mean by this?No need for you to worry about your money and be angry with me. You get it this afternoon.A. will B. shall C. may D. need 21.You _ come if you dont want to.A. wont B. neednt C. mustnt D. shant22.The order came that the medical supplies to Beijing for the H1N1 flu soon.Awould be sent Bshould send Cbe sent Dmust be sent23. Its hard to believe that Jack _ have fought with the policeman. Yes. If one _ ask for trouble, it cant be helped.A. would; willB. must; may C. should; must D. need; dare24. “Attention, please. Whoever can answer one of my questions_ receive a prize”, the teacher said in class. A. might B. shallC. shouldD. would 25.一Why didnt you come to Mikes birthday party yesterday?Well，I , but I had something important to do at the moment.Ashould Bmust Cshould have Dmust have26.Without the help of my English teacher, I the first prize in the English Speaking Compition.Awould win Bwould have won Cwould not winDwould not have won28. It is important to know about the cultural differences that cause problems.Amust Bdare Cneed Dmay29.Has Tim started? He said he would join in the party.He . He is a man of his word.A. could have left B. must have left C. cant come D. wont be coming30.Thank you for reminding me of the time, or I _ late yesterdayDont mention itAshould be Bwould beCwill have beenDwould have been31. -If you to my birthday party last Saturday, you would have met our old friend Jim . -I caught a cold, I had been walking around in the rain.Acame Bhad comeCwould comeDwould have come32. -I regret to say that I have shouted at you the other day.-Forget it. I was a bit out of control myself.Ashouldnt Bmustnt Ccouldnt Dmightnt33. The story is so descriptiveI feel as if I _ there. A. would be B. were C. am D. have been34_ the clouds, you would find the airplane in the sky easilyAHad it not been for BIf it were not CIf it had not been for DWere it not for35. Tom have come in personHe came such a long way just to tell us the resultAmustnt Bneednt Cwouldnt Dcouldnt36.But for their help, we _ the program in time.A. can not finish B. will not finish C. had not finished D. could not have finished37The driver tried everything he could think of, but the car just not moveAshould Bmight Cmust Dwould38I am not going to sit here and let her abuse meI demand that she immediately for what she just saidAapologize Bwould apologize Capologized Dmust apologize39 .-Can I pay the bill by check ? -Sorry, sir. But it is the management rules of our hotel that payment _ be made in cash. A. shall B. can C. will D. may40-Its really a pity that I didnt see you in Shanghai. - I _ to see you in the hotel, but I was too busy.AhopeBhadhopedChopedDamhoping 41_ it rain, the crops would be saved. AWillBShouldCWouldDCould42Rose _ tell her mother that she didnt pass the exam. Adare not toBdoesnt dare toCdoesnt dareDdares not43She insisted that she _ not guilty , but we insisted that she _ into prisonAwas; be put Bbe ; was put Cshould be; was put Dwas; should put44.Dont play with the dog, Jack, for it _ be dangerous at times. A. shallB. shouldC. can