情态动词的基本用法
情态动词本身虽有一定的意义,但它必须和实义动词一起构成谓语动词,表示说话人的语气和情态,情态动词后接动词原形。初中学过的情态动词有can, could, may, must, need, shall, should, will, would, have to等。
1. can / could
表示能力(等于be able to)或客 ( http: / / www.21cnjy.com )观可能性;还可以表示请求或允许;用在否定句、疑问句或感叹句中还可以表示惊异、怀疑、不相信的态度。Can / Could I ... 表示请求对方许可(用could比用can语气更加委婉和客气,但答语必须用can);Can / Could you ... 用来表示说话人征求对方意见(用could比用can语气更加委婉和客气)。
2. may
表示许可或允许,意为“可以”。May I ... 表示征求对方许可,否定回答一般用mustn’t或can’t。
3. must
意为“必须、应当”,表示义务、命令或必要; ( http: / / www.21cnjy.com )在回答must引出的问句时,肯定回答用must,否定回答用needn’t 或don’t have to,表示“没有必要”。
4. need
作情态动词时,多用于否定句或疑问句中,表示“需要”或“必要”(need用于肯定句时,常作实义动词,有人称和数的变化)。
5. shall
表示说话人征求对方的意见或向对方请示。
6. should
意为“应该”,表示义务、责任,可用于各种句式。
7. will
用于疑问句中,表示说话人向对方提出请求或建议;还可以用来表示做某事的意志、意愿、决心或打算。
8. would
表示过去的习惯性动作,有“总是、常常”的意思;还可表意愿、拒绝、请求等。
9. have to
意为“不得不”,强调客观需要,能用于多种时态;而must强调说话者的主观看法,没有时态变化。
【专项练习】
Ⅰ. 请从各题后所给的A、B、C、D四个选项中选出最佳答案。
( )1. —Must we clean the classroom now
—No, you___________.
A. must B. needn’t C. should D. can’t
( )2. You____________ be careful with fire when you have a picnic in the forest.
A. will B. must C. can D. may
( )3. —May I go surfing alone, Dad
—No, you____________. It is dangerous.
A. may not B. can’t C. needn’t D. don’t
()4. —Should I call Mary here right away
—No, you____________ . She is on the way here.
A. mustn’t B. can’t C. may not D. needn’t
( )5. — __________ you mind closing the door
—No, not at all.
A. Would B. Can C. May D. Should
( )6. I said I _________do anything for him.
A. would B. will C. have to D. need
( )7. —It’s a secret between us. Don’t tell anybody else.
— ____________.
A. I do B. I don’t C. I will D. I won’t
( )8. —You must come to the meeting on time.
—OK, I _____________.
A. must B. have to C. will D. should
( )9. At the age of seven, I ____________speak a little English.
A. have to B. could C. can D. should
( )10. Many of the s ( http: / / www.21cnjy.com )tars___________, because they are far away from us.
A. may not see B. can’t be seen
C. mustn’t be seen D. needn’t see
( )11. —Could I call you by the first name
—Yes, you _____________.
A. will B. could C. might D. can
( )12. —Must I return the book tomorrow morning
—No, you____________ . You __________ keep it for three days.
A. mustn’t; may B. mustn’t; must
C. needn’t; can D. needn’t; must
( )13. —May I go out to play basketball, Dad
—No, you __________. You must finish your homework first.
A. mustn’t B. may not
C. couldn’t D. needn’t
( )14. —Can you go swimming with us this afternoon
—Sorry. I ____________look after my little sister at home.
A. can B. may C. would D. have to
( )15. —Would you like to go fishing with me this afternoon
—I’d love to, ( http: / / www.21cnjy.com ) but I’m afraid I__________ . I have too much work to do.
A. can’ t B. mustn’t C. needn’t D. may not
( )16. —What a nice day! __________we go hiking
—Good idea.
A. Shall B. Must C. Need D. Will
( )17. We__________ keep the new traffic law and learn how to protect ourselves.
A. may B. should C. can D. could
( )18. —Must I come at four
—Oh, no, you ___________.
A. don’t B. mustn’t C. don’t have to D. can’t
( )19. ___________ you get me some paper, please
A. Shall B. May C. Need D. Will
( )20. —May I put my bike here
—No, you ___________. You __________put it over there.
A. may not; may B. needn’t; must
C. mustn’t; should D. won’t; should
Ⅱ. 请按要求完成下列各句,每空一词(含缩写)。
1. My brother can play chess. (改为一般疑问句)
__________ _____________ brother _____________chess
2. You should do the dishes. (改为否定句)
You___________ ____________ the dishes.
3. Could I open the window (作肯定回答)
______________ , ___________ ____________.
4. May I smoke here (作否定回答)
__________, __________ ___________ .
5. He must do it himself. (改为同义句)
He __________ __________ __________ it himself.
6. My sister can ride a bike.
(用when she was 10 years old改写句子)
My sister _________ __________ a bike when she was 10 years old.
7. You must sell your car. (改为一般疑问句并作肯定和否定回答)
____________ ____________ sell my car
Yes, you _____________. / No, you_____________ .
8. The boy is able to write with his left hand.(改为同义句)
The boy ___________ ___________ with his left hand.
参考答案
情态动词的基本用法专项练习
Ⅰ. 1-5 BBBDA 6-10 ADCBB 11-15 DCADA 16-20 ABCDC
Ⅱ. 1. Can your, pla ( http: / / www.21cnjy.com )y 2. shouldn’t do 3. Yes, you can
4. No, you can’t / mustn’t 5. has to do
6. could ride 7. Must I; must; needn’t 8. can write
情态动词表示推测
【要点提示】
情态动词表示推测是其重要用法之一。可用来表示推测的情态动词主要有must, can / could, may / might等。
肯定推测:
must, can / could ( http: / / www.21cnjy.com ), may / might都可以表示肯定推测。must 表示把握性极强的推测,意为“肯定、一定”;can / could和 may / might表示把握性不大的推测,意为“也许、可能”。
否定推测:
can’t 意为“不可能”,表示很有把握的否定推测,may not意为“可能不”,表示把握性不太大的否定推测。
【专项练习】
Ⅰ. 请从各题后所给的A、B、C、D四个选项中选出最佳答案。
( )1. A teacher __________also make a mistake if he or she is not careful enough.
A. must B. may C. should D. has to
( )2. —What are you going to eat for supper
—I__________ have noodles or rice.
A. need B. must C. may D. should
( )3. —Where’s Lucy
—I’m not sure. She_________ be in the school library.
A. need B. must C. may D. will
( )4. —Look! Mr King is on the other side of the street.
—It ___________be him. He has gone to Lanzhou.
A. mustn’t B. can’t C. shouldn’t D. won’t
( )5. Hurry up! Dad __________for us at the train station.
A. must wait B. must be waiting C. need wait D. need be waiting
( )6. —Tom. Don’ ( http: / / www.21cnjy.com )t drive too fast. You ___________hit the others’ cars.
—OK, I won’t, Mum.
A. must B. need C. might D. have to
( )7. —Whose book is this
—It ___________be Peter’s. He entered the classroom just now.
A. need B. could C. should D. will
( )8. —There _________ many animals in the park.
—You are right.
A. has to B. have to C. may have D. may be
( )9. —You mean this CD __________ belong to Victor
—Yes, it has his name on it.
A. must B. may C. might D. can
( )10. —There’s somebody at the door. It __________be Jim.
—It ___________be him. It’s just seven o’clock. It’s too early.
A. can; can’t B. will; won’t
C. should; mustn’t D. need; may not
Ⅱ. 请根据句意,从方框中选择适当的单词填空。
must, may, can’t
1. Such a businessman ( http: / / www.21cnjy.com )__________ be honest. He gets his money in such a dishonest way.
2. Mary’s par ( http: / / www.21cnjy.com )ents have bought a large house with a swimming pool. They
__________ be very rich.
3. —Excuse me, is this the right way to No. 10 Middle School
—Sorry, I’m not sure. It ___________be.
参考答案
情态动词表示推测专项练习
Ⅰ. 1-5 BCCBB 6-10 CBDAA
Ⅱ. 1. can’t 2. must 3. may