情态动词的用法 情态动词的基本用法特点 1） 情态动词 除 ought 和 have 外，后面只能接动词
原型。 2） 情态动词没有人称，数的变化，即情态动词第
三人称单数不加-s。 3） 情态动词没有非谓语形式，即没有不定式，分
词，等形式。
高中阶段都学过哪些情态动词呢 1 can / could / be able to 2 may/might 3 must / have to 4 shall / should 5 will / would 6
need / dare 7 ought to 1 can / could / be able to 1 Some of us can use computers now, but we
couldn't last year.（能力） 2 It will be sunny in the day time ,but it can
rain later on this evening（客观可能性） 3 ---Can I go now ? yes ,you can （请求和允许） 4 Could you wait a few days for the memory? （请求） 5 1 Can this news be true?
2 It can't be our headmaster.he has gone to
Beijing.（表推测，主要用于否定和疑问）
*be able to 能用于各种时态。
can / could 只能表示现在或过去的能力。
*was / were able to : “设法做成某事”
相当于
managed to do sth.
succeeded in doing sth.。 1. can 与be able to 有何区别？ 1. A computer ______ think for itself;
it must be told what to do.
A. can’t
B. couldn’t
C. may not
D. might not 2. The fire spread through the hotel very quickly but everyone ______ get out.
A. had to
B. would
C. could
D. was able to A
D
3. They will ______ run this machine on their own in three months. A. can
B. could
C. may
D. be able to D
2 may / might 1 May I watch Tv after supper?
Yes you may /No ,you mustn't.（请求许可) 2 It may be true ./ she may come tomorrow / He might have some fever（推测） 3 May you succeed ! May you have many
more days as happy as this one（祝愿） may/ might as well 还是 -----好 we may as well stay where we are 5. — Could I borrow your dictionary?
— Yes, of course you _______.
A. might
B. will
C. can
D. should 6.
— Might I watch TV after supper?
— Yes, you ________.
A. may
B. must
C. might
D. can C
A
3 must 语 have to 的 用法 1 You must come to school on time . You mustn't
waste any more time（必须,禁止） 2
Must I come back before ten ?
Yes ,you must.
No, you needn't./ don't have to 3 It must
be our headteacher.
You must be hungry after a long walk.（推测) 4 I really must go now.
I have to go now,because my mother is in
hospital.( 不得不） He must be reading, ____ he? You must do it yourself, ____ you? He must have gone over the article,
______he? It must have rained last night, _____ it? 3、表推测语气的反意疑问句的构成 isn’t don’t hasn’t didn’t 另外must 还有偏偏一定要的意思 why must you play the piano while others are sleeping. 7. You ______ return the book now. You can
keep it till next week if you like.
A. can’t
B. mustn’t
C. needn’t
D. may not 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 C
B
9. --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 10. --May I pick a flower in the garden?
-- ________.
A. No, you needn’t
B. Not, please.
C. No, you mustn’t
D. No, you won’t B
C
4 shall 与 should 1用于一，三人称疑问句表示征求对方的意见 和 向对方请示
Shall the driver wait ?What shall we do next ? 2 用于 二 三人称陈述句表示命令警告，允诺， 威胁以及法律条文规定 You shall go with me / He shall be punished
You shall have the book when I finish it All the children shall go to school at the age
of seven. 3表示劝告和建议 You should study hard. 4 表推测 They should have arrived by two o'clock 5用于if 条件句表示万一 Ask Tom to ring me up if you should see him. Shoud I be free tomorrow ,I will come. 6 表竟然 I don't know why you should be so rude to
your mother
Tom’s father promised, “You ___have a new computer if you pass the coming examination,”
A.can
B.should
C.shall
D.may
C
------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
B
You ought to have helped him with his English, ____you ?
A. won’t you
B. ought not you C. shouldn’t you D. wouldn’t you
C 5 will 与 would 的用法 1 表示意志和意愿 I will never do it again. They said that they would help us. 2 表请求，建议 Will you please take a message for me? Would you please pass him the book? 3 表功能 This machine won't work. 4 表示习惯性动作与used to有何区别 Fish will die without water. Every evening ,he would sit by the window. 6 need 语 dare的用法 既可做实意动词又可做情态动词。做情态动词用于 否定和疑问句而做实意动词可用于肯定，否定疑问 How dare you say such a thing?
How dare you to say such a thing? He daren’t to speak English before such a
crowd, did he?
He daren’t speak English before such a
crowd, dare he? She _____out alone at night.
(
)
A.dare not to go
B. dares not go
C. doesn’t dare to go
D. doesn’t dares go C 7 ought to 的 用法 1 表应该与 should 的 区别 You ought to take care of him. You are his father .You ought to get him
to receive good education
2 表推测 He ought to be home by now. He must be home by now. 一 情态动词+ 完成时表对过去的推测 1 must have done（仅用于肯定句) 2 can't /couldn't have done(用于否定疑问句） 3 may have done （肯定，否定均可) 4 might have done（肯定，否定均可)
二 表虚拟 1 should / could /would /might have done 三
needn't have done
would rather have done
had better have done
Jenny ____with him at that time, for I was having dinner with her in my home. (
)
A.can’t have been
B. mustn’t have been
C. must be
D. may be
A
They are disappointed at the English party. They say that it ___better organized. (
) A.had been
B. had to be C. must have been
D. could have been
D ---- Did you walked home by yourself last night ? ---- Yes, I did. But I think I _____.
(
) A.
needn’t
B. shouldn’t C. may not have
D. needn’t have D 8. We______last night, but we went to the concert instead. A. must have studied
B. might study C. should have studied
D. would study 9. There was plenty of time. She_____. A. mustn’t have hurried
B. couldn’t have hurried C. mustn’t hurry
D. needn’t have hurried 10. Yesterday, Jane walked away from the discussion. Otherwise. She____something she would regret later. A. had said
B. said C. might say
D. might have said.
C D D 11. ----Did you scold him for his mistake? ----Yes, but______it. A. I’d rather not do B. I’d better not do C. I’d better not have done D. I’d rather have not done D