2016年高考英语语法专题剖析课件：6-情态动词与虚拟语气.ppt

1、2016年高考英语语法专题剖析6.情态动词与虚拟语气一、情态动词的基本用法一、情态动词表示推测表示可能性的层次比较：词语肯定式否定式疑问式Must必定，必然/Should说话者有较大的试探性/ought to说话者有较大的试探性(含义同should)/can有时候可能不可能有可能吗could可疑的可能不可能语气比can弱may或许，也许，也说不定可能不/might比may还弱比may not还弱/(1)must常用于肯定句，一般不用于否定句和疑问句；can常用于否定句、疑问句或感叹句中，表示疑惑、惊讶或不相信等意思；could既可用于肯定句又可用于否定句和疑问句中。(2)would,could

2、,should,might不一定与过去时间有关，也可以表示可能性弱于与他们相应的现在时形式。(3)should/ought to表示推测时，表示确定或可能性大的期望，即合乎理想的情况或结果。(1)You be hungry alreadyyou had lunch only two hours ago!解析句意：两小时前你刚吃过午饭，你不可能已经饿了。根据后面的语境可推知前面是“不能够，不可能”，故用cant。cant二、情态动词表示请求、允许、允诺英语中表示请求、允许和允诺的情态动词通常有：can，may,could,might,shall,will和would等。1.Can I.?May

3、I.?Could I.？和Might I.？都可以表示征询听话人的许可。Could I use your bike tomorrow?明天我可以用一下你的自行车吗？Yes,you can.(No，Im afraid not.)可以的。(恐怕不行。)此处could，might不表示过去，而是表示更委婉的语气。肯定回答一般用Yes,please/Sure(Certainly/Of course)，you can(may)，不能用could和might。否定回答一般用mustnt或cannot，也可用may not,had better not，或者直接用No，Im afraid not.2.Wil

4、l/Would you.？表示请求。would表示更客气，有时也用Wont you.？意为“好吗？”“要不要”。Will you close the window？请你把窗户关上好吗？Wont you drink some more coffee?要不要再来一点咖啡？3.shall用于第一、三人称的疑问句中时表示征求意见。Shall I get you some tea？我给你倒点茶好吗？Shall the boy wait outside?让那男孩在外面等好吗？4.shall用于第二、三人称的陈述句时，往往表示给对方(you)或第三者(he,she,they)以允诺、命令、决心、警告或威胁等

5、，在法律、条约、协定等文件中可以表示义务、规定等。You shall get a birthday present.你会得到生日礼物的。(允诺)You shall be sorry for it one day,I tell you,有一天你会后悔的，我告诉你。(警告)Each citizen shall carry his identification card when travelling.旅游时每个市民务必带上身份证。(规定)(2)Will you read me a story,Mummy?OK.You have one if you go to bed as soon as pos

6、sible.解析句意：妈妈，给我讲个故事好吗？好，如果你尽快上床睡觉，我就给你讲一个。考查情态动词。shall在此处表示“允诺”。shall三、情态动词表示必要性表示“必要性”的情态动词通常有：must,should，ought to，have to。1.ought to与should意思大体相同，但ought to语气比should重，往往表示从法律或道义上“应该”。You are his father and ought to take care of him.你是他父亲，应当照顾他。(有责任，从道义上应该)Young people should show respect for the

7、old.年轻人应该尊重老年人。2.have to表示“必须，不得不”，这个意义与must很接近，但must表示主观意志，而have to表示由于客观因素不得不做某事。I told her that she must give up smoking.我叫她必须戒烟。I have to hand in my term paper before 5：00 p.m.today.我必须今天下午5点前交学期论文。(3)I dont care what people think.Well,you.解析句意：我不介意别人怎么想。噢，你应该那么做。根据语境可知，应用should，意为“应该”，表示一种建议，劝说

8、。should四、情态动词表示能力表示“能力”的情态动词有：can,could,be able to。1.情态动词can只有两种时态形式，现在时can和过去式could，而be able to有多种时态形式。Mary can play the piano.She has been able to play it since she was five.玛丽会弹钢琴，她5岁起就会弹了。2.表示过去能力时，was/were able to表示经过一番努力后取得了成功。相当于manage to do或succeed in doing，而could没有这个含义。Yesterday I was able

9、to get home before the heavy rain.昨天我在下大雨前赶到了家里。(4)The fire spread through the hotel very quickly but everyone(able)get out.解析was able to表示经过努力能够做到，强调成功。句意：大火很快蔓延了整个宾馆，但是大家都成功地离开了。was able tocan与be able to的区别(1)can只能用在一般现在时和一般过去时中，而be able to有更多的时态。(2)表示过去特定的能力或经过努力才具备的能力，只能用be able to。I talked with

10、 her for a long time,and finally I was able to make her believe me.我和她谈了很长时间，最终才赢得她的信任。(3)用在其他动词，如might,may,would后只能用be able to。用can,could,be able to的适当形式填空(5)Though the building was on fire,they go out safely.(6)Im going to Europe on vacation with John if I find the money.(7)Hows your new babysitte

11、r?We not ask for a better one.All our kids love her so much.(8)The police still havent found the lost child，but theyre doing all they.(9)You be too careful when driving.were able tocantcouldcancant五、“情态动词have done”的用法“情态动词have done”的常见用法包括：1.must have done表示对过去已发生的事情进行肯定的推断，只用于肯定句中，意为“一定，必定”，其否定形式为：

12、cant/cannot have done。It must have rained last night,for the road was quite wet.昨晚肯定下雨了，因为路面十分潮湿。I saw Mr Wang just now.He couldnt have gone abroad.刚刚我还看见王先生了，他不可能已经出国了。2.could have done意为“本来可以，本来能够”，表示虚拟语气。You could have made greater progress,but you didnt try your best.你本来可以取得更大的进步，但是你没有努力。3.may/m

13、ight have done表示对过去已发生的事情进行推断，意为“可能/或许已经”。其否定形式为：may/might not have done意为“可能没有做”。Its no use going to his house.He may not have gone home.He may have gone somewhere else.去他家没用。他可能没有回家，可能已经去了别的地方。4.should/ought to have done表示本应该做某事，却没有做，含有责备或后悔之意。其否定形式为should not/ought not to have done表示本不该做某事却做了。Wit

14、h all the work finished,I should have gone to the party last night.所有的工作都做完了，我昨晚本该去参加宴会的。You ought not to have made fun of him.He is not the one you laugh at but learn from.你本不应该取笑他的。他不是你要嘲笑的人而是你应该学习的榜样。5.neednt have done表示本没有必要做某事却做了，多用于否定句中。You neednt have waken me up；I dont have to go to work tod

15、ay.你本不必叫醒我的；我今天不上班。注意：neednt do表示“没有必要去做某事”，时间上应该是现在或将来。You neednt telephone him now,for he isnt at home.你现在不必打电话给他，因为他不在家。(10)Mark have hurried.After driving at top speed,he arrived half an hour early.解析考查“情态动词have done”的用法。neednt have done表示“本来不必要做但已经做了”，符合语境。neednt完成句子(11)I(我本来可以帮助你的),but I was t

16、oo busy then.(12)You(一定是睡得很晚)last night.Your eyes are red.(13)I(本应该做作业)last night,but I went to the cinema.could have helped youmust have slept lateshould have done my homework 六、情态动词的其他用法情态动词的其他用法主要有：1.情态动词need和dare的用法。(1)need和dare作情态动词时常用于否定句、疑问句或条件句中，无人称和数的变化，疑问句和否定句中不加助动词。Need I telephone him no

17、w?需要我现在打电话给他吗？She dare not go out alone at night.她晚上不敢一个人出去。(2)need和dare用于实义动词时，有词形变化。变成否定句、疑问句时，要加助动词。You dont need to do it yourself.你不必亲自做这件事。We should dare to give our own opinion.我们要敢于提出自己的观点。2.几个可以表示某一特定的语气或态度的情态动词(1)can可以用来表示惊异、怀疑、不相信的态度，主要用于否定句、疑问句或感叹句中。How can you be so careless？你怎么这么粗心？(2)

18、must用于条件句或疑问句中，可以用来表示责备、抱怨的感情色彩，意为“偏要，硬要”。Why must you be so late?你为何非要这么晚来呢？(3)may表示愿望、祝福时，有“但愿，祝”之意。May you succeed！祝你成功！(4)should表示惊讶，不以为然等情绪，用于某些句型中，多译为“竟然”。It seems unfair that this should happen to me.这种事情竟然发生在我的身上，好像不公平。(5)will的用法will表示“意愿，意志”，would表示过去时间的“意愿、意志”。will还可以表示某种倾向或习惯性动作，意为“总会，老是”

19、，其否定结构意为“不肯，不能”。I will do anything for you.我愿意为你做任何事。The door wont open.这门打不开。Every time she was in trouble,she would go to him for help.每次遇到麻烦她都会向他求助。3.情态动词的一些习惯用法(1)cannot/can never.too或 cannot.enough表 示“无 论 怎 么也不过分；越越好”。You cannot be too careful.你越细心越好。(2)cannot help doing./cannot help but do./ca

20、nnot but do.表示“禁不住；不得不”。I couldnt help jumping up when I saw him.一看到他我情不自禁地跳了起来。I cannot but admire his bravery.我不得不佩服他的勇敢。(3)“may/might as well动词原形”表示“还不如，不妨”，相当于had better。It is very late,so you may/might as well go to bed.夜深了，你不妨去睡吧。(14)If you go,at least wait until the storm is over.解析句意：如果你偏要走，

21、至少要等到暴风雨停了。考查情态动词的用法。If you must do sth为固定用法，意为：如果你偏要做某事。must(15)The door open,no matter how hard Grandma pushed.解析句意：无论Grandma如何推，门总是打不开。will表示某种倾向或习惯性动作，意为“总会，老是”，其否定为“不能，不肯”，在此是过去时态，故用“wouldnt”。wouldnt虚拟语气的考查要点一、虚拟语气用于条件状语从句1.表示与现在事实相反的假设，条件状语从句中的谓语动词 用 一 般 过 去 时(be动 词 用 were)，而 主 句 中 的 谓 语 动 词 用

22、“would/should/could/might动词原形”。If I were you,I would buy that house.If he had time,he should go with you.2.表示与过去的事实相反，条件状语从句中的谓语动词用过去完成时，主句中的谓语动词则用“would/should/might/couldhave过去分词”。If he had taken my advice,he would have succeeded in passing the examination.3.表示与将来事实相反，条件状语从句中的谓语动词用一般过去时或“should/we

23、re to动词原形”，而主句中的谓语动词则用“would/should/could/might动词原形”。If it were to rain tomorrow,the football match would be put off.4.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。If they had worked hard,they would be very tired now.(从句说的是过去，主句指的是现在)用所给动词的适当形式填空(1)If I(have)time next week,I would go to the p

24、arty.(2)If I(be)you,I should go and see the dentist at once.(3)If you had arrived at the station ten minutes earlier,you(catch)the train.hadwerewould have caught二、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。(1)“wish宾语从句”表示不能实现的愿望，译为“要是就好了”等。表示现在不能实现的愿望，从句中的谓语动词用一般过去时；表示将来不能实现的愿望，从句中的谓语动词用“would/could动词原形”；表示过去不能实现的愿

25、望，从句中的谓语动词用“had过去分词”或“could/shouldhave过去分词”。I wish it were spring all the year round.I wish I had known the answer.I wish I could fly like a bird.(2)在表示建议、要求、命令等动词后的宾语从句中，谓语动词用“should动词原形”，should可以省略。常见的动词有：suggest,advise,propose,demand,require,insist,request,command,order等。She suggested we(should)l

26、eave here at once.The doctor ordered she should be operated on.suggest除了“建议”外，还有“暗示，表明”的意思，若当“暗示”时，suggest后跟陈述语气。insist当“坚持主张、要求”时后跟虚拟语气；若当“坚持一说法、事实”时，后用陈述语气。2.虚拟语气在同位语从句和表语从句中的运用。表示建议、要求、命令等的名词，如advice,idea,order,demand,plan,proposal,suggestion,request等，其后的表语从句和同位语从句中谓语动词用“(should)动词原形”，should可以省略。

27、His suggestion that we(should)go to Shanghai is wonderful.My idea is that they(should)pay 100 dollars.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，表示惊奇、不相信、理应如此等。It is necessary(important,natural,strange,etc.)that we(should)clean the room every day.It was a pity(a shame,no wonder,etc.)that you

28、(should)be so careless.It will be desired(suggested,decided,ordered,requested,proposed,etc.)that she(should)finish her homework this afternoon.用所给词的适当形式填空(4)Where are the children?The dinners going to be completely ruined.I wish they(not be)always late.(5)It is requested that Class Two(give)a perfor

29、mance at the English evening.(6)He insisted that a deadline(set)for completing the task.were not(should)give(should)be set三、虚拟语气在其他场合的运用1.虚拟语气在as if/as though,even if/even though等引导的表语从句或状语从句中，如果从句表示的动作发生在过去，用过去完成时；指现在状况，则用一般过去时；指将来状况则用过去将来时。He did it as if he were an expert.Even if she were here,sh

30、e could not solve the problem.2.虚拟语气用于定语从句中。这种从句常用于句型“It is(high)time(that).”中，定语从句的谓语动词用一般过去时(be用were)或“should动词原形”，意思是“(现在)该”。Its time that I picked up my daughter.Its high time we were going.在It is time that.should动词原形.结构中，should不能省略。3.虚拟语气用在if only引导的感叹句中。If only I were a pilot.If only I had tak

31、en his advice.4.虚拟语气在一些简单句中的运用。(1)情态动词的过去式用于现在时态时，表示说话人谦虚、客气、有礼貌或语气委婉，常出现在日常会话中。It would be better for you not to stay up too late.Would you be kind enough to close the door?(2)用于一些习惯表达法中。Would you like a cup of tea?I would rather not tell you.(7)Dont handle the vase as if it made of steel.解析句意：拿花瓶时

32、不要认为它好像是由钢铁做的。as if“仿佛，好像”。花瓶并非由钢铁制作，与事实相反，故用虚拟语气。又因前面动词“Dont”可知是与现在事实相反，故用were。were易错点1 情态动词have done结构的误用用括号内动词的适当形式填空What a pity!Considering his ability and experience,he_(do)better.解析句意：真是遗憾！考虑到他的能力和经验，他当时有可能做的更好些。might have done【即时小练】The weather turned out to be fine yesterday,I_(take)the troub

33、le to carry my umbrella with me.解析句意：昨天天气结果很好，我本没必要那么麻烦拿伞的。neednt have taken“本没必要带结果带了”。neednt have taken以题说法此题容易误用must have done结构表示对过去已经发生的事情进行推测，意为“一定做了”；might have done结构表示过去本有可能发生某事，但实际上并未发生，是一种虚拟表达。突破指南情态动词have done结构是英语中的常考热点，熟记其意义，运用到适当语境中为关键。易错点2 几个情态动词的特殊用法易错点(辽宁卷)Peter be really difficult

34、 at times even though hes a nice person in general.解析句意：尽管Peter从整体上不错，但有时确实不好相处。情态动词can除了表示能力，意为“能够”，还可以表示“(有时)可能”的含义，这是can的一个很重要的用法。can【即时小练】(1)If the wound become swollen,do not hesitate to call me.解析句意：万一伤口肿了的话，要马上告诉我。should表可能性有“万一”之意，故用should。(2)I think Ill give Bob a ring.You.You havent been i

35、n touch with him for ages.解析分析句意可知，表示原则上或道义上“应该”的情态动词should用在这里正合适。shouldshould以题说法本题易误用must。must常译为“必须”，常指说话者主观要求“必须”。突破指南我们要善于归纳一些情态动词的常考点。情态动词can在高考英语中的出现率很高，它的其他常考用法如下：can可以表示能力，表示客观的可能性；表示请示和允许；表示惊异、怀疑、不相信的态度；主要用于肯定句、否定句和疑问句中。用于肯定句表推测时，指理论上的可能性，并不涉及是否真的发生。should的一些常考点也要铭记在心。should除了可以表示原则上或道义上“应该”外，还可以表示推测含义，意为“估计(是)”“按理应当”等含义。这种用法的should是一个常考知识点，考生应重视。should另外一种用法是意为“竟然”，表示吃惊的语气。