情态动词总结.doc

情态动词专题
情态动词表示说话人的语气和态度。如需要、愿意和怀疑等。它们有一定的词义，但不完整，必须和主要动词的原形一起构成谓语，常用的情态动词有：can, could, may, might, must, have to, ought to, should, will, would, need, dare, shall, , be able to及半情态动词had better, would rather, have to, would like to.
情态动词的基本用法：
一、 can
1. 表示能力“能……， 会……”
A computer can’t think for itself; it must be told what to do.
2. 表示许可，“能够……， 可以……”；在疑问句中表示请求许可“能不能……，要不要……，用could表委婉语气，还可以用may。
You can go out to play when you finish your homework.
--Can /Could /May I go now ?—Yes, you can/may.
Could you give me a lift to the station?
3. 表示猜测，通常用在疑问句中，表示惊讶、怀疑；用于否定句中，表示有把握的否定推测 “不可能……”
Who can it be ?那会是谁呢？ Can it be true? 那会是真的吗？
She can’t be waiting for you. 她不可能在等你。
He can’t have gone there alone.他不可能独自一人到那儿去。
4.（表示平时大部分时间不是这样，只是偶然发生）“有时候会……”。
Some equipment at home can be dangerous to children.
Peter can be really hard to get along with even though he is a nice person in general.
特别记忆：
① can not/ can never…too… 或 cannot … enough“再……也过分，越……就越好”
You can never be too careful （you can’t be careful enough ）while crossing the street.
②can’t help doing sth.= can’t help but do sth = can’t but do sth =can do nothing but do sth.
When a close friend dies, you can’t but feel sad.
③were /was able to do sth. 表示过去设法成功地做了某事，could没有此意
The fire spread through the hotel very quickly, but everyone was able to get out.
④can’t/couldn’t have done 不可能做过… ；could have done 本来能够做，（却没做成）
I could have worked out the problem，but I was too nervous.
--- A man answered the phone. I suppose it was her husband.
--- It couldn’t have been her husband. He had been dead for ages.
二、may
1. （表示许可、请求允许）可以……，might比may 的语气更委婉。否定回答常用mustn’t.
-- May/might I use your camera? No, you mustn’t / I am afraid you can’t.
-- Yes, you may.(Yes, please.) .
You may not take photographs in the museum.
2. may表示把握性不大的猜测，“或许， 可能”，might可能性更小。may not 可能不…
I might see you again — who knows?
Things might not be so bad as they seem.
He may not come this afternoon, I am not sure.
3. （表示愿望、祝福）愿……，祝……。用倒装语序。
May you succeed! May you be happy! May you return in safety!
★ may/ might have done.对过去动作不大有把握的推测，“也许已经…”
★ might have done本来可能…，但实际上没有发生。
You shouldn’t have climbed the hill. You might have killed yourself.你本不该爬那山的，你或许会摔死的。
★ may/might as well do…不妨……的好、 还是……的好。
Since it’s a fine day, we might as well take a walk.
★ may well do 很可能……,完全有理由……
He may well be proud of his son.
三、must
1. （表示义务、必要性、命令）必须，得，要。回答must的问句时，否定式用needn’t或don’t have to. “mustn’t” 表示禁止、不可以。
——Must I wash the dishes at once?
——Yes, you must./No, you needn’t.( No, you don’t have to.)
We mustn’t waste our time.
2. （表示固执、不满）偏偏，硬要，偏要
Why must you make such a big noise while your sister is sleeping?
★ 表示绝对的有把握的肯定推测，“一定”“准是” must be doing sth.一定正在做某事;
must have done对过去动作的推测；注意其后的反疑疑问句形式。
There must be a mistake, isn’t there ?
He must be watching TV at home, isn’t he?
He must have seen the play, hasn’t he?
You must have gone to the cinema last night, didn’t you?
★ have to ( have got to) 强调客观需要，而且有人称、时态、数的变化。
You will have to wait until the manager comes back.
I had to work when I was your age.
四、shall
1. 用于疑问句中, 第一、第三人称，表示说话人征求对方的意见或向对方请示。
Shall we go out for a walk? 我们出去散步好吗？
Shall he come in or wait outside? =Do you want him to come in or wait outside? 要他进来还是在外面等候？
2. 用于陈述句中，第二、第三人称，表示说话人的警告、强制、命令、要求、允诺或威胁。
You shall fail if you don’t work hard.（警告）
He shall get the book when I finish reading.(允诺)
3.（用于法律、规则等条文中）应……、须……、得……
No person shall smoke or carry a lighted cigarette, cigar in this area.
五、should
1. （表义务、责任）应该
You should apologize to him.
2. （表预期）应该会，想必会， 一定会……吧
The photos should be ready by 12:00.
It’s almost seven o’clock now. They should be at home.
3. （表惊讶、遗憾）竟然、居然
I am surprised that a well-- dressed gentleman should speak so rudely.
It‘s strange that Tom, the most excellent student in our grade should fail in the exam.
4. Why/How+ should+…? 结构表示说话人对某事不理解、感到意外、惊异等，意为“竟然”。
I don’t know why you should think that I did it.我真不知道你凭什么认为这件事是我干的。
5. 用于某些表示建议、命令、请求的动词（如insist, order, demand, advise, suggest, recommend, propose, require, request, command, desire等）后的宾语从句中，谓语为（should ）+ v 。这类词的名词后的同位语从句、表语从句也用（should ）+ v
I suggested the meeting (should) be put off.
My suggestion is that the meeting( should) be put off.
It is suggested that the meeting (should) be put off.
★ ought to / should have done过去本应该做却没有做某事含有责备之意; should have done也有惊讶之意“居然……。
I told Sally how to get there, but I should have written it out for her.
I was surprised she should have won the first prize in the competition.
★ oughtn’t to / shouldn’t have done过去本不该做却做了某事。
I was really anxious about you. You shouldn’t have left home without saying a word.
六、will 与would
1. 表示意志、愿望、决心、习惯、倾向性。
I will never do that again.
I will do the work if she will do it with me.
He will sit there for hours without doing anything.
Man will die without air and water.
2. 用于第二人称表示请求、建议等，would比will 委婉、客气。
Would you pass me the book? Won’t you come and sit for a while?
3. 临时做出的决定.
- -Do you know Jones is in hospital ?--Oh, I didn’t know. I will go to see her this afternoon.
4. 过去反复发生的动作或某种倾向用would。
During the vacation, he would visit me every week.
When I was young, I would sit under the old tree listening to grandpa tell me stories.
5. won’t /wouldn’t 表示主语不具有某种功能，“就是不肯……，不能……”
The machine won’t work. The car wouldn’t move , no matter how hard I pushed it.
七、dare与need
1. need表示“需要”、“必须”作情态动词时，仅用于否定句和疑问句中；在肯定句中作实意动词后接不定式。
Need I finish the work today?---Yes, you must /have to.
★ needn’t have done意为“本来没必要做却做了”。
As it turned out to be a small house party，we needn’t have dressed up so formally.
2. dare 作情态动词主要用于疑问句、否定句和条件句中。用作实意动词时，在否定句中后边的to可以省略.
He daren’t speak English before such a crowd, dare he?
He doesn’t dare (to) ask me questions.
★ would like to do sth. 想做某事, would like/ love to have done 本来想做却没有做成
I would like to have come to your birthday yesterday, but I was busy preparing a report.
情态动词之高考题选：
1. —I left my handbag on the train，but luckily someone gave it to a railway official.
—How unbelievable to get it back! I mean，someone ________ it.
A. will have stolen B. might have stolen C. should have stolen D. must have stolen
2. --Write to me when you get home.
--Yes, ____ .
A . I must B. I should C. I will D. I can
3. --Are you coming to Jeff’s party?
--I’m not sure, I ____ go to the concert instead.
A. must B. would C. should D. might
4. --Will you stay for lunch?
--Sorry, ____ . My brother is coming to see me.
A. I mustn’t B. I can’t C. I needn’t D. I won’t
5. --When can I come for the photos? I need them tomorrow afternoon.
--They ____ be ready by 12:00.
A. can B. should C. might D. need
6. -- I stayed at a hotel while in New York .
--Oh, did you ? You ___ with Barbara.
A. could have stayed B. could stay C. would stay D. must have stayed
7. The fire spread through the hotel very quickly but everyone ___ get out.
A. had to B. would C. could D. was able to
8. Johnny , 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
9. --Is John coming by train?
--He should , but he ___ not. He likes driving his car.
A. must B. can C. need D. may
10. A left luggage office is a place where bags ____ be left for a short time especially at a railway station.
A. should B. can C. must D. will
11.-- Isn’t that Ann’s husband over there?
--No, it ___ be him. I’m sure he doesn’t wear glasses.
A. can’t B. must not C. won’t D. may not
12. —May I take this book out of the reading room?
—No，you ________.You read it in here.
A. mightn’t B. won’t C. needn’t D. mustn’t
13. --- You needn’t take an umbrella. It isn’t going to rain. --- Well, I don’t know. It_____
A. might B. need C. would D. should
14. He ________ sleep, although he tried to, when he got on such a hunt for an idea until he had caught it.
A. wouldn’t B. shouldn’t C. couldn’t D. mustn’t　　　　
15. When I was a child, I ______ watch TV whenever I wanted to.
A. should B. could C. must D. need
16. Harry is feeling uncomfortable. He _____ too much at the party last night.
A. could drink B. should drink C. would have drunk D. must have drunk
17. The children _____ lost in the woods; otherwise, they would have been at the lakeside camp as scheduled.
A. must have got B. must get C. should have got D. should get
18. —Why are your eyes so red? You _______ have slept well last night. —Yeah, I stayed up late writing a report.
　 A. can’t B. mustn’t C. needn’t D. won’t
19. No one _____ be more generous; he has a heart of gold.
　　A. could B. must C. dare D. need
20. Since nobody gave him any help, he _____ have done the research on his own.
　 A. can B. must C. would D. need
21. The door ____ open , no matter how hard she pushed.
A. shouldn’t B. couldn't C. wouldn't D. mightn't
22. I ________ myself more—it was a perfect day.
A. shouldn’t have enjoyed B. needn’t have enjoyed C. wouldn’t have enjoyed D. couldn’t have enjoyed
23. It _____be the vocabulary that caused you the problem in the exercise because you know a lot of words.
A. may B. couldn’t C. should D. needn’t
24. If we _____ a table earlier, we couldn’t be standing here in a queue.
A. have booked B. booked C. book D. had booked
25. Eye doctors recommend that a child’s first eye exam ______ at the age of six months old.
　　A. was B. be C. were D. is