1、第2讲情态动词与虚拟语气考点1情态动词的基本用法1. can/could(1)表示能力，意为“能，会”。I cant promise anything, but Ill do what I can.我不能许诺什么，但我会尽力而为。(2)表示请求，意为“能，可以”。Can/Could you help me with it?你能帮我一下吗？(3)表示许可，意为“能，可以”。(4)表示推测，意为“可能”，常用于疑问句及否定句中。2. may/might(1)表示请求、许可，比can正式。May I use your computer? 我可以用一下你的电脑吗？(2)表示推测，谈论可能性，might
2、表示语气更不肯定，意为“可能，或许”，一般用于肯定句中。He might get there in time, but I cant be sure.他有可能准时到达，但我不敢肯定。(3)表示希望、祈求、祝愿，通常用“may主语v.”。May all of our wishes come true.愿我们所有的愿望都能实现。3. must(1)表示主观看法，意为“必须”，肯定回答用must，否定回答用neednt或dont have to。Must I give up smoking?我必须戒烟吗？Yes, you must./No, you neednt/you dont have to.是
3、的，你必须。/不，你不必。(2)表示坚持，意为“偏偏，偏要”。Must you make so much noise?你非得弄出这么多噪声吗？(3)表示有把握的推测，意为“一定，肯定”，用于肯定句中。He must be waiting for us.他一定在等我们。(4)mustnt表示禁止，不表示推测。 We mustnt let the water run to waste.我们不能让水白白流掉。4. need(1)need表示需要，主要用于否定句和疑问句中，其否定形式为neednt, 意为“不必”。用need提问时，肯定回答为must，否定回答为neednt。 Need I go wi
4、th you?我需要和你一起去吗？Yes, you must./No, you neednt.是的，你必须。/不，你不必。(2)need还可以作实义动词，此时有人称、数和时态的变化，如果是人作主语，后面多接动词不定式。He doesnt need to do it. 他不必做这件事。5. daredare意为“敢，敢于”， 有两种词性：(1)dare作为情态动词，多用于否定句、疑问句或条件句中，后接动词原形。 I dont know whether he dare say that to him. 我不知道他是否敢对他说那件事。(2)dare作为实义动词，此时有人称、数和时态的变化 。 He
5、doesnt dare to interrupt.他不敢插嘴。6. shall(1)用于第一人称，表示将要做某事。 I shall travel to New York by air this weekend.这个周末我将要乘飞机去纽约旅行。(2)用于第一、三人称，表示征求对方意见。 Shall the driver wait outside?司机在外边等着可以吗？(3)用于第二、三人称，表示说话人给对方的命令、警告、允诺或威胁。 It has been announced that candidates shall remain in their seats until all the pa
6、pers have been collected.据宣布，在所有试卷收上来之前，考生必须留在自己的座位上。7. should(1)表示劝告、建议、责任、义务等，意为“应该”。I should go and visit him this afternoon, but I wonder if I will be free.今天下午我应该去看望他，但我不知道我是否有空。(2)表示推测，意为“按理说应当”。Its nine now and everyone should be here.现在九点了，大家应该都到了。(3)表示“竟然”。Its strange that he should be late
7、.真奇怪，他竟然会迟到。(4)表示“万一”(条件句)。 If it should rain tomorrow, I wouldnt go.万一明天下雨，我就不去了。8. will/would(1)表示意愿。They wont lend us any more money.他们不愿再借给我们钱了。 (2)表示请求。Will/Would you do me a favour?请帮我一下，好吗？(3)表示真理，意为“总是”。Oil will float on water.油总是浮在水面上。(4)will表示现在的习惯，would表示过去的习惯，意为“常常做某事”。 He would get up e
8、arly when he lived in the country.他住在乡下时总是早起。(5)表示要求，意为“一定”。would和used to都可表示过去的习惯，但前者表示过去反复的动作，常与every day, often, frequently等连用；后者表示过去的状态或过去的习惯，但现在已不存在。When he was abroad, he would read as many books as possible.在国外时，他总是尽可能多读书。She doesnt get up so early as she used to.她不像以前那样起得那么早了。【技巧点拨】若句中谓语动词为原
9、形，在其前设纯空格题时，注意考虑情态动词。然后根据句意或句式结构填入恰当的情态动词。考点2情态动词表示推测可能性可分为客观的可能性和具体事情实际发生的可能性两种。1. 客观的可能性并不表示具体某事是否会发生，而用来说明人或事物的特征。情态动词can可用于肯定句中表示客观的(或理论的)可能性；而表示具体事情实际发生的可能性时， can一般不用于肯定句。Accidents can happen on such rainy days.在这样的多雨天气里可能会发生事故。(表示客观的可能性)We may go to the cinema tonight, but we are not sure yet.
10、 今晚我们可能去看电影，但还没确定。(表示实际可能性，不用can)2. 表示具体事情实际发生的可能性表示具体事情实际发生的可能性的层次(由强及弱)比较：情态动词用法must表示肯定的推测，一般只用于肯定句中，意为“一定；必定” should/ ought to表示推测的可能性比较大，表示有依据或有前提的推测，仅比must的可能性小一点，意为“按说应该”can/could用于疑问句中，意为“可能”；用于否定句中，意为“不可能”。could表示推测时，语气比can弱may/might用于肯定句中表示不十分肯定的推测，意为“有可能”；用于否定句中，意为“可能不”，表示一种不太确定的语气。might表
11、示推测时，语气比may弱(1)在肯定句中表示推测(must/have to, should/ought to, may, might, could)当说话者表达怀疑或犹豫之意时，需用may, might或 could, 其中might, could比may所表达的怀疑或犹豫之意更强。That may be our taxi now!现在那辆可能就是我们的出租车了！That could/might be our taxi (but I doubt it)那辆有可能是我们的出租车(但我有所怀疑)。当说话者表达毫无疑问的结论时，需用must和have to (较通俗)，意为“一定，肯定”；shoul
12、d和ought to所表达的程度不如must强，但比may, might和could强，should/ought to表示推测出合乎理想的情况或结果，意为“按说应该”。He must/has to be the wanted man: Hes exactly like the one in this picture. 他一定是被通缉的那名男子：他和这张照片上的人一模一样。He ought to/should be here on time he started early enough.他应该按时到这里他出发得够早的。(2)在否定句中表示推测(may not, might not, shoul
13、dnt, cant, couldnt)否定语气较弱时，常用should not (应该不会)，或用may not, might not (可能不，也许不)；否定语气较强时，则用cant或couldnt (不可能)。Dont worry. Your father may not have been hurt seriously.别担心，你父亲也许伤得不厉害。 There shouldnt be any difficulty in getting you a visa.给你办张签证应该不会有什么困难。(3)在疑问句中表示推测(can, could)can, could在疑问句中，常表示困惑、不相信
14、等。Theres someone outside who can it be?外面有人会是谁呢？What can they be doing?他们可能在做些什么呢？Could he be serious?他是认真的吗？Where can she have put it?她能把它放在哪儿呢？考点3“情态动词have done”的用法1. 对过去发生的事情或状态进行推测must have done sth.“(过去)一定做了某事”；语气比较肯定；用于肯定句may/mighthave done sth.“(过去)可能/也许做了某事”；语气不确定；用于肯定句和否定句can/couldhave done
15、 sth.“本能够做某事”；用于否定句和疑问句，表示对过去发生的行为的怀疑或不确定Looking at the large empty apartment, I became aware of how lonely my mother must have been in Brazil herself.看着这个又大又空的公寓，我开始意识到妈妈独自一人在巴西一定很孤单。The boy might have known the truth, but I am not quite sure.那个男孩也许知道了真相，但我不是很确定。I didnt see her in the meeting room
16、this morning. She couldnt have spoken at the meeting.我今天上午在会议室时没看见她，她不可能在会议上讲话。2. 表示“与过去事实相反”could have done sth.过去本可以做某事但实际上没做neednt have done sth.过去本不必做某事但实际上做了ought to/should have done sth.过去本应该做某事但实际上没做oughtnt to/shouldnt have done sth.过去本不应该做某事但实际上做了might have done sth.过去可能做某事但实际上没做He could hav
17、e gone on regretting it, as too many of us do.他本可以继续为此而遗憾，正如我们中很多人一样。I neednt have taken the umbrella, for the weather is fine.天气这么好，我本没必要带雨伞的。She really ought to have retired long ago, but shes still working.她早就该退休了，可她还在工作。You might have given him more help, though you were busy.你本可以给他更多帮助，虽然你很忙。考点
18、4虚拟语气一、if条件句中的虚拟语气虚拟情况虚拟条件句主句从句与现在事实相反主语should/would/could/mightdoif主语动词过去式(be动词用were)与过去事实相反主语should/would/could/mighthave doneif主语had过去分词与将来事实可能相反主语should/would/could/mightdoif主语动词过去式/were to do/should doIf the new safety system had been put to use, the accident would never have happened.要是新的安全系统被
19、投入使用的话，这起事故就不会发生了。We would be back in the hotel now if you didnt lose the map.如果你没有把地图丢了的话，我们现在就回到旅馆了。Grace doesnt want to move to New York because she thinks if she were to live there, she wouldnt be able to see her parents very often.格蕾丝不想搬到纽约，因为她认为如果住在那里，她就不能经常看到她的父母了。(1)如果表示虚拟语气的if从句中含有were, had
20、或should，可将if省略，然后将were, had或should移至主语之前。(2)如果主句和从句是对不同时间的事实的虚拟，则被称为错综虚拟语气。此时主句常有明显的时间状语。二、含蓄条件句的虚拟语气有时假设的条件不通过条件状语从句表达出来，而是隐含在某些词或短语中，或隐含在上下文中，这叫含蓄虚拟语气。常用的这类词或短语：without, but for, otherwise, or等。Do you have Bettys phone number?你有贝蒂的电话号码吗？Yes. Otherwise, I wouldnt have been able to reach her yesterd
21、ay.有，不然我昨天就联系不上她了。三、 虚拟语气在从句中的运用1. 在名词性从句中的运用(1)在表示要求、命令、建议、请求等动词后的宾语从句中，以及这些动词的名词形式后面的同位语或表语从句中的谓语动词用“(should)动词原形”。常见的此类动词：insist, order, command, require, demand, request, suggest, advise, propose, recommend等。My parents request that all the cleaning work (should) be finished this morning.我父母要求今天早
22、晨完成所有的清洁工作。当suggest作“暗示，表明”，insist作“坚持认为”讲时，从句要用陈述语气。(2)在“It is/was形容词/过去分词that . ”句型中，从句中的谓语动词用“(should)动词原形”。常见的形容词或过去分词：important, necessary, suggested, ordered, advised, requested, demanded等。It is necessary that we (should) clean the room every day.我们每天打扫房间是有必要的。It is required that middle school
23、 students (should) take at least one hours exercise every day.中学生被要求每天至少进行一个小时的锻炼。(3)wish后的宾语从句中的谓语动词的形式可用动词过去式，“had过去分词”和“could/might/would动词原形”，分别表示与现在、过去相反的情况和与将来情况可能相反。I wish that I had met that film star yesterday.我真希望昨天见到那名影星。(4)在would rather所接的宾语从句中，从句的谓语如果表示现在或将来要发生的动作，从句用一般过去时；如果表示过去发生过的动作，
24、从句用过去完成时。We would rather our daughter stayed at home with us, but it is her choice, and she is not a child any longer.我们宁愿女儿待在家，陪在我们身边，但是选择权在她手上，毕竟她不再是个孩子了。2. 三个固定句式中的虚拟语气句式虚拟情况虚拟现在虚拟过去虚拟将来if only引导的条件句及感叹句动词过去式had过去分词would/could/might动词原形as if/though引导的表语从句及方式状语从句动词过去式had过去分词would/could/might动词原形It
25、 is (high)time that .动词过去式或“should动词原形”It was John who broke the window. Why are you talking to me as if I had done it?打破窗户的是约翰。为什么你说得好像是我打破的似的？It is high time that we took/should take some measures to solve the problem.确实到了我们应该采取一些措施解决这个问题的时候了。当as if/though引导的句子所叙述的是真实的或极有可能发生或存在的事实时，从句要用陈述语气。【技巧点拨
26、】在虚拟语气中，关键词的意义和句意是判断句子是否为虚拟语气的重点，解答此类题目要重点考虑时间和主从句结构两个方面。. 单句语法填空1. (2021新高考卷)The hot spring at the foot of the mountain is something you must try after the climb. 2. (2021全国甲卷)The wall is 12 meters high and from here you can see (see) streams of people moving inside and outside the City Wall.3. (20
27、20天津卷5月)You shouldnt have scolded him for his poor performance. After all, he had done his best.4. (2020天津卷7月)We cant put off buying a new printer for our company. The one we have doesnt work.5. (2019天津卷)Kate heard a mans voice in the background, but she couldnt make out what he was saying. 6. (2019
28、天津卷)The workers were not better organized, otherwise they would have accomplished (accomplish) the task in half the time. 语法填空(2021福建福州一中模拟)Wherever you look these days, somethings looking back at you. There are video cameras on street 1. corners (corner), vehicles and our own front doors.A Chicago
29、company 2. called (call) Cooler Screens believes that you wont mind if they put cameras into the display cases (展柜) in stores. The cameras arent placed there 3. to prevent (prevent) you from stealing. Instead, theyre part of a system that tries to guess 4. what you will buy next, based on how you lo
30、ok.The doors on the cases 5. are (be) video screens that show images of the goods, so a customer can see whats available inside. The screens also show vivid ads. They decide which ads to show by 6. studying (study) video images of the customers.A camera feeds images of each customer into a computer
31、7. that/which guesses his or her sex and age.In addition, the system tracks 8. exactly (exact) where the customer is looking. Do the eyes come to rest 9. on/upon a bottle of Red Bull, or does the shopper fancy Coca Cola? The Cooler Screens system instantly 10. analyses (analyse) all of this data, an
32、d then starts showing ads on the cooler door. 写作运用根据汉语提示补全下面写作， 注意情态动词的运用。Dear Mr Brown，Im really glad to receive your email. As you have seen, many Chinese choose to stick the character Fu on the door upside down during the Spring Festival. 1. This can express their best wishes for the new year (这能
33、表达他们对新年的美好祝愿). In Chinese, the character for “upside down” sounds the same as the character “to arrive”， so this means that happiness is arriving. 2. This must be interesting (这一定很有趣), isnt it?By the way, Id like to invite you to celebrate the Dragon Boat Festival with my family 3. if you will come (如果你愿意来). Its a day in memory of the great poet Qu Yuan and we usually eat zongzi and enjoy dragon boat races. Itll be a good opportunity to experience Chinese culture and traditions.Looking forward to your reply.Yours，Li Hua
