1、专题八 情态动词与虚拟语气一、常用情态动词的用法比较典例(2011湖南十二校第二次联考，31)Can I paythe bill by check?Sorry,sir.But in our hotel payment _ bemade in cash.Aneed BcanCwillDshall解析：D。句意：我能用支票付账单吗？很抱歉，先生。在我们旅馆，只能用现金付款。考查情态动词。shall用于陈述句中的第二、第三人称，表示说话人的意图、允诺、警告、命令、决心等。如：He says he wont go,butI say he shall.他说他不去，但我说他必须去。二、情态动词have过去
2、分词的用法“情态动词have过去分词”结构被普遍认为是一个难点，因为它们表示的意义各不相同，可谓错综复杂。有些表示推测(表推测时，有的常用于肯定句，有的常用于否定句、疑问句)；有些表示责备等。要弄清楚它们之间的区别，必须理解每一种结构表示的意义：1“musthave过去分词”表示对过去发生的动作或存在的状态进行推测。只用于肯定句，意思是“一定已经”。The teacher must have thought Johnson was worth itor she wouldnt have wasted time on him,I suppose.2“may/mighthave过去分词”表示对过去
3、发生的动作或存在的状态进行不太肯定的推测。“mighthave过去分词”还可用于虚拟语气，表示与过去的事实相反。Where is my dictionary?I remember I put it hereyesterday.You might have put it in the wrong place.(推测)If he had worked harder he might have succeeded.(虚拟语气)3“can/couldhave过去分词”表示对过去事情的推测，意思是“可能已经”，常用于否定句和疑问句；“couldhave过去分词”还可用于虚拟语气，表示与过去事实相反。My
4、 MP5 player isnt in my bag.Where can I have putit？(推测)If he had come yesterday,I could have told him aboutit.(虚拟语气)4“neednthave过去分词”表示过去没有必要做某事却做了，含有“本来不必”之意。There was plenty of time.You neednt have hurried.时间很多，你本来不必那么慌慌张张的。(实际上是慌慌张张来的)5“should/ought tohave过去分词”表示过去本应做某事但没做，含有责备之意。I told your frien
5、d how to get to the hotel,but perhaps Ishould have driven her there.6“wouldhave过去分词”用于虚拟语气，表示与过去的事实相反。If I had not told him about the thing,he would neverhave known it.(虚拟语气)点拨考生解题时要把握好两点：是推测还是虚拟；是肯定句、疑问句，还是否定句。拓展对现在事情的推测，表示“一定，肯定”时用must动词原形。Hi,Jane.Any idea where Tom is?He must be in the workshop.I
6、 saw him there justnow.链接“should/ought tohave过去分词”的否定式表示过去本来不该做某事但做了。My cat is really fat.You shouldnt have given it so much food.拓展“had better have done”表示对过去最好做了某事而没有做的一种遗憾，其否定式为“had better not havedone”。You had better not have scolded her.would like/love to have done表示过去想做某事但未做I would love to hav
7、e gone to the party last night but Ihad to work extra hours to finish a report.三、虚拟语气.非真实条件句的虚拟语气警示：(1)若条件句中有were,had,should，可把if省略，而把were,had,should放在主语前，形成倒装结构，这种结构主要用于书面语中。Had you taken my advice(If you had taken myadvice),you wouldnt have failed in the examination.如果你听了我的建议，你就不会考试不及格了。(2)有时主句和虚拟
8、条件从句的动作发生的时间不一致，此时，主句和从句的谓语动词要根据各自所指的不同时间选择适当的动词形式。If you had worked hard,you would be very tired now.如果你真的努力工作了，你现在就会感到很累的。(从句指过去，主句指现在)(3)有时虚拟条件并不通过条件从句表达出来，而是通过词、短语或上下文暗示，此时句子的时态要依具体情况而定。Without electricity(If there were no electricity),life would be quite different today.如果没有电，今天的生活就会完全不同。He wou
9、ld have given you more help,but he was toobusy.他本来会给你更多的帮助，但是他太忙了。也就是说，如果那时他不忙，他可以给你更多的帮助。句中的but(he was too busy)实际上暗示了一个虚拟的条件如果那时他不忙。He would lose weight,but he eats too much.他本来可以减肥的，但是他吃得太多了。也就是说，如果他吃得不多的话，他是可以减肥的。句中的but(he eats too much)实际上暗示了一个虚拟的条件如果他吃得不太多。典例(2011福建卷，34)Pity you missed the lec
10、tureon nuclear pollution.I_it，but I was busy preparing for a jobinterview.AattendedBhad attendedCwould sattendDwould have attended解析：D。本题考查虚拟语气。句意：你错过了有关核污染的演讲真是遗憾。我本想去听来，但我忙着准备工作面试。由语境可知，此处表示“本想去而事实上没去”。为虚拟语气，叙述与过去事实相反，要用wouldhave done，故D项正确。2“should动词原形”表示的虚拟语气这一类型常见词有“一坚持(insist)、二命令(order,comman
11、d)、三 建 议(advise,suggest,propose)、四 要 求(request,require,demand,desire)”。以上词及其派生名词所接的名词性从句都使用“(should)动词原形”的虚拟语气。Janes pale face suggested that she was ill,and hermothersuggestedthatshe(should)haveamedicalexamination.Jane苍白的脸色表明她病了，她母亲建议她去检查身体。She insisted that the man had stolen her car and thathe(should)be sent to prison.她坚持说那个男人偷了她的车，并坚决要求他坐牢。3特殊句式中的虚拟语气Wish/Its(high)time(that).IIf only/Would rather等固定句式要求用相应的虚拟语气。I wish I could fly.真希望我能飞。I would rather you came tomorrow.我宁愿你明天来。If only I had taken your advice!要是听从了你的建议该多好啊！