高考英语语法单选归纳情态动词和虚拟语气 4页

‎2016年高考英语语法单选归纳（情态动词和虚拟语气）‎ 一、情态动词 I.情态动词基本用法 情态动词 用 法 否定式 疑问式 简答式 can 能力（体力，智力，技能）‎ 允许或许可（口语中常用）‎ 可能性（表猜测，用于否定句或疑问句中）‎ can not / cannot /can’t do Can…do…?‎ Yes,…can.‎ No,…can’t.‎ could couldn’t do may 可以（问句中表示请求）‎ 可能，或许（表推测）‎ 祝愿（用于倒装句中）‎ may not do ‎ May…do…?‎ Yes,…may. ‎ No,…mustn’t/can’t.‎ might might not do Might…do…?‎ Yes,…might No,…might not.‎ must 必须，应该（表主观要求）‎ 肯定，想必（肯定句中表推测）‎ must not/mustn’t do Must…do…? to.‎ Yes,…must.‎ No,…needn’t/don’t have have to 只好，不得不（客观的必须，有时态和人称的变化）‎ don’t have to do Do…have to do…?‎ Yes,…do. ‎ No,…don’t.‎ ought to 应当（表示义务责任，口语中多用should）‎ ought not to/oughtn’t to do Ought…to do…?‎ Yes,…ought. ‎ No,…oughtn’t.‎ shall 用于一三人称征求对方意见 用于二三人称表示许诺、命令、警告、威胁等 shall not/shan’t do Shall…do…?‎ Yes,…shall. ‎ No,…shan’t.‎ should 应当，应该（表义务责任）‎ 本该（含有责备意味）‎ should not/shouldn’t do Should…do…?‎ will 意愿，决心 请求，建议，用在问句中would比较委婉 will not/won’t do Will/Would…do…?‎ Yes,…will. ‎ No,…won’t.‎ would would not/wouldn’t do dare 敢（常用于否定句和疑问句中）‎ dare not/daren’t do Dare…do…?‎ Yes,…dare.‎ No,…daren’t.‎ need 需要,必须（常用于否定句和疑问句中）‎ need not/needn’t do Need…do…?‎ Yes,…must. No,…needn’t.‎ used to 过去常常（现在已不再）‎ used not/usedn’t/usen’t to do didn’t use to do Used…to do…?‎ Did…use to do…?‎ Yes,…used. ‎ No,…use(d)n’t. ‎ Yes,…did. ‎ No,…didn’t.‎ II.情态动词的重点知识 表示“能力、许可”的can 表示能力的情态动词用can/could A computer_____think for itself; it must be told what to do.‎ A.can’t B.mustn’t C.may not D.might not 和may 表示许可时用may/might ,can/could 都可以，但在问句中用could…?或might…？ 以使口气委婉客气，其回答一定要用can或may，以使回答口气明确（must表示一定，必须，mustn’t表示禁止，不许可）。‎ ‎①—Could I call you by your first name? —Yes, you______‎ A.will B.could C.may D.might ‎②Johnny, you_____play with the knife, you_____hurt yourself.‎ A.won’t/can’t B.mustn’t/may ‎ C.shouldn’t/must D.can’t/shouldn’t 在肯定句中could不可以用来表示过去某一特定场合的能力，而要用was/were able to。‎ The fire spread through the hotel very quickly but everyone_____get out.‎ A.had to B.would C.could D.was able to 表示“推断、判断”的can may,must 在肯定句中都可以用来表示可能。在含义上must语气最肯定,may表示的是事实上的可能性。‎ Peter______come with us tonight, but he isn’t very sure yet.‎ A.must B.may C.can D.will 而can表示的是逻辑上的可能性：‎ Mary is in poor health. She can be ill at any times.‎ 在否定句中只能用can和may。所以can’t时用以代替mustn’t，语气比may更肯定。中文可以翻译为不可能。‎ Michael______be a policeman, for he’s much too short.‎ A.needn’t B.can’t C.should D.may 在疑问句只能用can，不能用may和must。‎ He may be very busy now. Can he be very busy now?‎ He must be very busy now. Can he be very busy now?‎ need need作为情态动词只有一种形式，只用于否定句和疑问句。‎ dare dare作为情态动词用时有两种形式：dare和dared两个词形，除了可以用于否定句和疑问句外，还可以用于条件从句或表示怀疑的句子中。‎ If he dare come,I will kick him out. I don’t know whether he dare say.‎ 注意:He doesn’t dare(to)answer the question.（否定句）‎ Does she dare(to)enter the dark room?（疑问句）‎ shall 用于第一人称：征求对方的意见。‎ What shall we do this evening?‎ 用于第二、三人称：警告、命令、允诺、威胁等。‎ You shall fail if you don’t work harder. 警告 He shall have the book when I finish reading.允诺 He shall be punished.威胁 should 劝告、建议、命令、应该做、道义上的责任。‎ You should(ought to) go to class right away. ‎ I should(ought to) help him because he is in trouble.‎ will/would 请求、建议，would比will委婉客气。‎ Would you pass me the book?‎ 表示意志、愿望和决心。‎ I will never do that again. ‎ They asked us if we would do that again would可表示过去反复发生的动作或某种倾向。‎ During the vacation he would visit me every week The wound would not heal.（伤口老是不能愈合）‎ would表示估计或猜想。‎ It would be about ten when he left home. ‎ What would she be doing there?‎ 情态动词+have done的用法 could+have done：本可以做而实际上未能做。‎ You could have done better, but you didn’t try your best.‎ cannot+ have done：表示对现在或过去行为的否定推测。‎ He cannot have been to that town.‎ can+主语+ have done：表示对过去行为的怀疑或不肯定（用在疑问句中）。‎ Can he have got the book?‎ might(may)+ have done：对过去发生的行为不太肯定的推测。‎ He may not have finished the work.‎ If we had taken the other road, we might have arrived earlier.‎ must+ have done：对过去发生的行为肯定的推测。‎ 其否定式为：cannot have done。‎ You must have seen the film.‎ You cannot have seen the film.‎ needn’t+ have done：本来不必要做的而实际上又做了。‎ You needn’t have watered the flowers,for it is going to rain.‎ 注意：didn’t need to(have to)do：‎ 没有必要做而实际上也没有做 I didn’t need to clean the windows.My sister did it 2 hours ago.‎ should(ought to)+ have done：本来应该做而实际上又没有做。其否定形式表示某中行为不该发生却发生了。‎ You should have started earlier, but you didn’t.‎ She shouldn’t have taken away my measuring tape,‎ for I worked to use it.‎ 注意：He should have finished the work by now.（表推测）‎ 二、虚拟语气 类 别 用 法 例 句 If引导的 条件从句 与现在事实相反 从句动词：过去式（be用were）‎ 主句动词：should/would/could/might+do If he were here, he would help us.‎ 与过去事实相反 从句动词：had+done 主句动词：should/would/could/might+have+done If I had been free,I would have visited you.‎ 与将来事实相反 从句动词：过去式/should+动词原形/were+to do 主句动词：should/would/could/might+动词原形 If it should rain tomorrow, we would not go camping.‎ 省略if的虚拟条件句 将虚拟条件从句中的were，had,should放到主语之前，构成主谓倒装 ‎①Should he come ,tell him to ring me up.‎ ②Were I you,I would not do it.‎ ③Had I been free,I would have visited you.‎ 混合虚拟条件句 不同时间的虚拟：各遵守各的规则 ‎①If he had listened to me, he would not be in trouble now.‎ ②If he had told me yesterday,I should know what to do now.‎ ③If I were you, I would have gone to her birthday party.‎ 虚拟与陈述的混合：各遵守各的规则 ‎①He could have passed the exam,but he wasn’t careful enough. ‎ ②You should have come earlier.The bus left a moment ago.‎ 含蓄虚拟 条件句 but for+名词表示虚拟条件 句子或主句中的谓语动词的形式视具体情况而定。这是考查考生应变能力的最佳试题。‎ ‎---But for your timely warning,we ______ into great trouble.‎ ‎---You know we’re friends.‎ A. would get B. must have got ‎ C. would have got D. can’t have got without+名词表示虚拟条件 Without the air to hold some of the sun's heat, the earth at night would be freezing cold.‎ 动词不定式表示虚拟条件 It would be only partly right to follow in this way. 如果用这种方式，仅仅对了一半。‎ 现在分词表示虚拟条件 Having known in time ,we might have prevented the accident.要是及时得知的话，我们也许能阻止这场事故。‎ 过去分词表示虚拟条件 Given more attention, the tree could have grown better. 如果多留心的话，这树本来可以长的更好。‎ 副词otherwise表示虚拟条件 I was too busy at that time.Otherwise,I would have called you.我当时太忙，否则我就给你打电话了。‎ 连词but连接的句子表示虚拟条件 He _____fatter but he eats too little .‎ A. would become B. would have become ‎ C. must become D. must have become ‎ 其它 状语从句 as if/as though引导的状语从句中动词用did或had＋done或would／could／might＋do。‎ 注意：as if/as though引导的状语从句中也可以用陈述语气：‎ 当说话者认为所述的是真实的或极有可能发生或存在的事实时：‎ It sounds as if it is raining．听起来像是在下雨。 He talks as if he is drunk．从他谈话的样子来看他是醉了。‎ ‎①与现在事实相反 He talks as if he knew where she was．‎ ②与过去事实相反 He talks about Rome as if he had been there before.‎ ③与将来事实相反 He opened his mouth as if he would say something.‎ in order that/so that引导的状语从句中动词用can/could/may/ might/ would等+do Turn on the light so that we can see it clearly.‎ 宾语从句 demand, suggest, order, insist后接的从句中动词为should+do He suggested that we not change our mind.‎ wish后的从句中分别用过去式，过去完成式和should/would+do表示与现在，过去和将来情况相反 I wish I could be a pop singer.‎ I wish I would have gone to Shanghai last month.‎ 主语从句 在It is necessary / important / strange that…‎ It is suggested / demanded/ ordered / requested that…等从句中，‎ 谓语动词用should+do It is strange that such a person should be our friends.‎ 其它 句型中 It is time that…句型中动词用过去式或should+do It’s high time that we left/should leave.‎ would rather所接的从句中动词用过去式或者过去完成式 I would rather you stayed at home now.‎ If only句型中动词常用过去式或者过去完成式，表示强烈的愿望 If only our dream had come true!‎