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. |
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| 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. |
| 表示“能力、许可”的can和may | 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 |
| 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 |
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| 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 |
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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 |
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| 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? |
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| 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 |
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| 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 |
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| 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） |
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| would表示估计或猜想。 |
It would be about ten when he left home. What would she be doing there? |
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| 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. |
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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. |
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| 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. |
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| 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） |
| 类 别 | 用 法 | 例 句 | ||
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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. = 2 \* GB3 ②Were I you,I would not do it. = 3 \* GB3 ③Had I been free,I would have visited you. |
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| 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. = 2 \* GB3 ②If he had told me yesterday,I should know what to do now. = 3 \* GB3 ③If I were you, I would have gone to her birthday party. |
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| 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. = 2 \* GB3 ②You should have come earlier.The bus left a moment ago. |
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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 |
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| 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。 |
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| 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。 |
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| 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 |
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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 \* GB3 ②与过去事实相反 He talks about Rome as if he had been there before. = 3 \* GB3 ③与将来事实相反 He opened his mouth as if he would say something. |
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| 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. |
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| 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. | ||
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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! | |||
1．—You didn’t invite Mary to theball?
—____ her, too?
A．Must I invite B．Should I have invited
C．Must I have invited D．Should I invite
1B考查情态动词的用法。“should have done sth．”结构表示“本该做但事实上并未做某事”。另外注意第一句的陈述语序后面用问号表示疑问的语气，意思是“难道你 …？”
2. _____ it rain tomorrow, we would have to_______ the picnic.
A. Would; put forward B. Should; call off
C. Will; give up D. Should; put up
2B考查虚拟语气及固定短语的含义。第一空should表虚拟语气，第二空取消野餐。句意：万一明天下雨，我们就会取消野餐。
3．I would have helped you, but I __ really occupied the whole week．
A．was B．am C．had been D．were
3A考查动词时态和语气。 would have helped you表与过去事实相反的虚拟语气。but后面是事实句。答案选A，表过去的实际情况。
4. “Dear, if you listen to me, you ______ have some candies as a reward,” thewoman told her little son.
A.shall B. do C. should D. must
4A考查情态动词的用法。此处shall表示“许诺”。
5．—Can I pay thebill by check?
—Sorry, sir．But it is themanagement rules of our hotel that payment _____be made in cash．
A．need B．will C．shall D．can
5C考查情态动词。此题中的themanagement trules决定答案选C。因为表根据书面规定、法律条文及合同的要求必须干某事用shall。
6. —She looks very happy.
— I guess so. It’snot difficult after all.
A. should B.could C. must D. might
6C考查情态动词表推测。此处must表示对过去有把握的推测，She musthave passed the exam. 她肯定通过了考试。
7. Look at the naughty boy! You ______ havetaught him how to behave himself.
A. must B. may C.can D. should
7D考查虚拟语气。此处should have done表示“应该做的事没做”。句意：你应该教他如何规矩些。
8．But for the storm, we __________a pleasant journey, but had to turn back halfway．
A．would have B．would have had C．will have D．had
8B考查虚拟语气的用法。“but for”表示“要不是 … ”，后面常跟虚拟语气结构。此题是对过去的动作或状态进行虚拟，所以用“would + have + donesth．”表示。
9.Mary failed the driving test again．If she ______ harder,she ______ the test easily．
A．practiced; would pass
B．had practiced; would pass
C．had practiced; would have passed
D．should practice; should have passed
9C考查虚拟语气。此句表示与过去的事实相反。句意：如果她努力些，她就会轻松通过驾照考试。故选C。
10. The missing children haven’t been foundyet. Something terrible ________ to them.
A. may happen B. should have happened
C. must happen D. might have happened
10D考查情态动词表推测。句意：那些失踪的孩子还没有找到。一些可怕的事情可能在他们身上发生了。
11．I ________ up early thismorning, so I stayed in bed until 8 o’clock a．m．
A．needn’t have got B．didn’t need to get
C．shouldn’t have got D．can’t have got
11B考查情态动词及虚拟语气的用法。此处need用作行为动词时，前面用助动词do表示否定或者疑问。此句中的didn’t need to get up表示“没有必要而未做某事”；needn’t have donesomething表示“做了一件没有必要做的事”；shouldn’t have done sth．表示“做了不应该做的事”，是一种表示责备的语气；can’t have done sth．表示否定的推测。
12．— What’s the matter with Peter?
— He was seen crying when he was coming out of the office．He ________ by the manager．
A．may be scolded B．should have been scolded
C．must be scolded D．must have been scolded
12D考查情态动词的用法。“must + have + 过去分词”，表示对过去某事或某种情况的肯定的猜测，只能用于肯定的陈述句。
13．These achievements_______without the contribution of Qian Xuesen, a key leader of the New China'snuclear, missile and so on．
A．would have been unthinkable B．would not be unthinkable
C．would be unthinkable D．would not have been unthinkable
13A考查虚拟语气。题干句子中“without the contribution of QianXuesen”表示与过去事实相反的虚拟语气，谓语动词要用“would（not）have done'’。
14. You ____have written so long an article.The teacher said 100 wordswould be enough.
A.mustn’t B needn’t C couldn’t D nwouldn”t
14.B考查情态动词。Mustn’t 禁止；needn’t没必要；couldn’t不能；wouldn’t《过去》不乐意。
15. You use your cell phone here in ourhospital because of the disturbance to the electronic equipments! It’s forbidden.
A. shouldn’t B. may not C. needn’t D. mustn’t
15D考查情态动词的用法。句意：我们医院禁止使用手机，因为它会电子仪器产生干扰。此处mustn’t表示“禁止”。
16. It is dangerous to play with the knife. You ______ hurt yourself.
A. can B. may C. must D.should
16B考查情态动词表推测。此处may表示可能性小的一种推测。
17. “Without Chinese toys, kids around theworld ________ not have so much happiness.” said an European Union official.
A. would B. should C. will D. shall
17A考查情态动词的用法。句意：一位欧共体官员说：“如果没有中国玩具，全世界的孩子就不会再有这么多的欢乐。”根据句意选A。
18.If you write something and send itimmediately by email, which you ___later regret, there is no chance for secondthoughts．
A．would B．should
C．have to D．might
18D考查情态动词表推测。此处you might later regret意为：你可能以后会后悔。
19. The woman boss told the customer that it was none of her businessand ordered that he _____ away at once.
A. went B. go C. goes D. going
19B考查宾语从句中的虚拟语气。此处order后用should do的形式，should可以省略。
20. — ________ you break this $ 100 bill for me?
— Justa moment. I will see if I _______.
A. May ; can B. Can ; can C.Will ; will D. Should ; may
20B考查情态动词的用法。第一个空中can表示请求，第二个空中can表示能力。
21．—Did you visit Italythis winter holiday?
－No．We it，but we spent too much time shopping in France.
A．could have visited B．must have visited
C．shall have visited D．need have visited
21A考查动词的虚拟语气。表示与过去的事实相反用could/should/wouldhave done的形式。句意：我们本能去参观意大利的，但我们在法国购物的时间太长了。
22. If itwere not for the fact that she _______ play tennis, I would invite her to joinus.
A. couldn’t B. shouldn’t C. might not D. can’t
22D考查情态动词的用法。此处can’t表不能，that she can’tplay tennis 是the fact的同位语从句。同位语从句讲得是事实，故用can’t。
23. ---Jennytook the 9:10 bus to Hangzhouthis morning.
---Really? She ____ the 9:00 Express. It is much more comfortable and faster totravel by train.
A. could have taken B.need have taken
C. must have taken D.would have taken
23A考查虚拟语气。句意：----珍妮今天早上乘了9:10的公共汽车去杭州。----真的吗？她本能乘9:00的特快火车的。乘火车更加既更加舒适和快速。根据句意选A。
24.Even if you are an experienced teacher, you sometimes ____ make somemistakes.
A. can B. must C. should D.will
24A考查情态动词的用法。句意：即使你是一位有经验的老师，你有时也会犯错误。情态动词can表示理论上的可能性，意为：可能会。
25．Most hotels in Sanya were full during the Spring Festival, butfinally
we finda room in a small guesthouse near the seaside.
A. ought to B.could C.might D.were able to
25D考查情态动词的用法。此处were able to表示“能做到且做到了”；could表示“能做到”。
26.How ___ I helpthem to understand when they won’t listen to me?
A．can B．would C．may D．must
26A考查情态动词的用法。句意：既然他们不听我的，我怎么能帮助他们理解呢？此处can表能力。
27.You spent 300 yuan on a pair of cotton gloves. Such a pair of cottongloves______be worth so much.
A.mustn't B. wouldn't C. can't D. needn't
27C考查情态动词的用法。Can表推测用于否定句，故选C。句意：一副这样的手套不可能值这么多钱。
28．It isusually not quite cold in this area in March，butsometimes temperature_____be low．
A．should B．must C．can D．shall
28C考查情态动词的用法。此处can在肯定句中表推测，表示理论上的可能性。句意：有时温度可能会低。
29．If transportcosts into consideration at the beginning , thefactory would have been built far from its present place.
A．will be taken B．were taken C．had been taken D．were being taken
29C考查虚拟语气及短语的含义。根据从句与过去的事实相反可知用过去完成时。
30. KidZania is anindoor park that lets children try out the professions
they choosein the future.
A. must B.should C. might D. can
30C考查情态动词的用法。句意：KidZania是一个室内公园，这个公园让孩子们尝试他们未来可能选择的职责。根据句意选C。
