情态动词(讲解版)

情态动词定义： 表示说话人的情绪、态度或语气的动词叫情态动词。 情态动词语法特征 1）情态动词不能单独作谓语，没有人称，数的变化，即情态动词第三人称单数不加-s。

2）情态动词的否定式是在情态动词后面直接+not。 3）情态动词的疑问式是把情态动词提到主语前。 主要情态动词 can, could（be able to） may, might must （have to） will, would 情态动词的用法 I.

can/ could

shall, should ought to need dare

1. ___Can___ you speak Japanese? Just a little. 2. Only the judge ___can___ save her from prison. 3. I ___could___ drive a car before I left middle school. 4. It was so dark that I ___could___ see nothing. Note: 表能力、有权力 （could是can的过去式）

5. --___Can/Could ___ I go home now? --Yes, you can. –No, you can’t. 6. --___Can/Could___ I speak to Andrew? 7. You ___can’t___（not）smoke here.

Note: （口语）允许、请求，表可以 (could非can的过去式，表委婉)

8. It ___can___/could ____ be very cold here, even in spring. 9. She is clever, but she ___can___/could___ be dull sometimes. Note: （表示偶然现象发生的可能性）有时会，时而可能

10. It ___can’t___/couldn’t___(not) be my father. He is abroad now.

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11. There is someone outside. Who ___can___ it be?

12. You __can’t/couldn’t have seen him__ (not see) him. He was not there. 13. She __ can’t/couldn’t have been ___(not be) more than six then.

14. He __ can’t/couldn’t have finished___ (not finish) the work last night without your help.

Note: 表推测（否定、疑问句）

15. He __could have told__(tell) me the answer but he refused to. Note: 过去本能做而没有做

16. You _cannot/ can never_________ do the work too well. 17. You _cannot /can never__ be careful enough in your study. Note: cannot…too; can never... too; cannot enough再…都不为过；越…越好

can & be able to

区别：1. can 只有两种时态 现在时can & 过去时 could be able to 有各种时态

2. 用于一般所具有的能力，可以互换，但是当表示成功做到时，通常用

be able to或manage to

1. He _can/is able to_ write music.

2. We shall __be able to__ finish the work soon. 3. I haven’t _been able to_ find the book.

4. He _could/was able to__ swim like a fish when he was young.

5. I talked with her for a long time and finally I __was able to_ make her believe me.

6. The fire spread through the building quickly but everybody ___was able to /managed___ to escape. II.

may/might

--Yes, you __may__./Yes，please. --No, you __may not /can’t/mustn’t___. 2. He asked if he _might_____ use the phone.

3. We start early so that we _may/might___ arrive in time. Note: （允许、请求）可以 1. --__May___ I leave now?

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4. __May__ you be happy all your life. Note: 祝、愿

5. John is absent. He __may/might_____ be ill.

6. It _may/might______ rain tomorrow or it __may/might_____ be merely cloudy. 7. I can’t find my book. I _may/might have left___(leave) it in your office just now. 8. You know this story very well. You _may/might have read___(read) it before. Note: 表推测

9. We start early so that we ___may ___ arrive in time.

10. I wrote down his telephone number so that I ___might___ remember it. Note: 表目的（用于目的状语从句中）

maybe & may be

11. He ___may be ___ here. I’m not sure. 12. ____Maybe______ you should call him. 13. –Are you going out tonight? -- ____Maybe____. III.

must

1. You __must___ have a passport if you want to go abroad. 2. Drivers __mustn’t___ drive after drinking. Note: （义务、责任、强制、命令）必须应该

3. You _must_______ first finish your homework before you watch TV. 4. --_Must________ I come tomorrow? --Yes, you __must____.

--No, you __needn’t/ don’t have to_____.

Note: （说话者主观上的意愿、建议、命令等）应该、必须、务必

5. Winter __must___ be followed by spring. 6. All living things ___must___ die.

Note: 表示客观规律不可避免性或必然性，注定要，必然（只用于肯定句）

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7. You __must___ be ill. I can see it from your face.

8. You __must have read___(read) the book. You know the story very well. 9. There’s much noise from next door. They __must be having__(have) a party. Note: 表肯定推测 Must & have to

区别：1. have to 用于各种时态，还可和其它情态动词连用 2. have to 表示因客观环境的迫使而不得不做某事 1. -- Let’s see a movie tonight.

--I’d love to, but I __have to____ take care of my mom. 2. They __had to__ speed up, for the weather turned terrible. 3. They will ___have to ___ get up early tomorrow. 4. We may ___have to___ put off the plan.

5. You ___don’t have to ___ tell him about it.不一定要 6. You ___mustn’t ___ tell him about it. 一定不要 IV.

shall

1. I __shall________ ring you as soon as I arrive. Note: 将来时（第一人称）将要、会

2. __Shall______ I open the window for you? 3. Let’s go to the cinema tonight, __shall___we?

Note: （在问句中表示说话人征求对方意见或提出建议，用于第一、三人称）…好么

V. should & ought to

1. We hoped that we __should______ be able to do that. Note: 用于过去将来时

2. You _should/ought to____ be more careful next time. 3. _Should____ I call him and apologize?

Note: (表示建议、劝告、命令、要求) 应该，必须 （ought to 语气强）

4. It’s 4:30. They __should______ be in New York by now. Note: (表示说话者根据一定的依据猜测、推测、推论等)该，可能

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5. You _should have told__(tell) me earlier about it, but you didn’t.

6. You __shouldn’t have done_________ (do) that to your mother, but you did. Note: 过去按理该…而实际没有…（常有责备、埋怨、惋惜之意） VI. will

1. He _will____ come back soon. Note: 将来时

2. I hope you __will____ succeed. 3. I __will____ do my best to help you.

Note: （表意愿、决心、承诺）要、愿、想、会、保证

4. When he is in trouble, he __will______ turn to his coach for help. 5. I _will___ turn you out of doors if you don’t keep quiet. Note: 状语从句

VII. would

1. He told us that he __would______ meet us at the airport. Note: 过去将来时

2. --__Would______ you mind my smoking?

--Yes, _please don’t. /You’d better not. _______________. ---No, __go ahead______________ Note: 提出请求、邀请（委婉）

3. I __would________ like to see a film tonight. 4. I _would____ rather not leave you here.

5. _Would __ you please _not smoke____(not smoke) here? Note: 意愿、决心、喜欢等

6. He _would_________ be delighted if I went to see him. 7. If you had come earlier, you _would have seen__(see) him. Note: 条件句（虚拟）

8. When he was young, he __would__often __walk___ (walk) in these woods.

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Note: （表过去习惯性、经常性的行为或动作）总是

VIII. need (情态动词没有过去式)

Note: 1) need 作实意动词，有人称、时态和数的变化

2) need 作情态动词，只能用在否定句和疑问句中，没有人称、时态和数

的变化

need sth don’t need sth Do … need sth ? need to do don’t need to do Do …need to do… ? needn’t do Need …do …? 1. He __needs to_________(go) there now.

2. He _need not/ doesn’t need to go__ (not go) there now.

3. --__Need_/Does ______he ____go_/need to go___(go) there now? -- Yes, he _must__/does______. --No, he _needn’t_/doesn’t________.

4. He needs to finish the work by Friday, ___doesn’t______ he? 5. He needn’t stay there, __need_______ he?

6. He __needn’t have given_____ (not give) her so much money at the time, and now he regrets it.

Note: needn’t have done过去本不必做却做了

need doing & need to be done 7. I _need to__ (repair) the computer.

The computer __needs repairing_____.(repair) The computer __needs to be repaired____(repair)

IX. dare （情态动词有过去式dared）

Note: 1) dare作实意动词，有人称、时态和数的变化

2) dare作情态动词，只能用在否定句和疑问句中，没有人称和数的变化, 但

有过去时。

dare to do don’t dare to do Do …dare to do… ? dare not do Dare…do …?

1. He __dares to say__(say) what he thinks.

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2. He __dare not say_/doesn’t dare to say______(not say) what he thinks. 3. --__Dare_/Does _____he __say_/dare to say____(say) what he thinks? --Yes, he __dare/ does_________. --No, he __dare not/ doesn’t______. 4. How __dare_____ you say(say) so?

5. I __dare__ you ___to climb_____(climb) the tree. Note: dare sb. to do sth.谅某人也不敢做某事

6. I __dare say________(say) things will improve. Note: I dare say我敢说，我认为，很可能，恐怕 补充：

1．情态动词表猜测时，不同的“肯定”程度依次排列如下：  He is at home. ( 事实 ）

 He must be at home.（ 非常可能）  He should be at home.（ 很可能 ）  He may be at home.（ 仅仅可能 ）  He might be at home.（ 或许 ）  He isn’t at home.（ 事实 ）

 He can’t be home.（ 接近肯定 ）

 He couldn’t be at home.（ 不及 can’t 肯定 ）  He may not be at home. （ 可能 ，但不肯定 ）  He might not be at home.（ 不及 may 肯定 ）。

2．情态动词+ have done

could have done （本能做而没做…）

can’t / couldn’t have done （不可能已经做了…） must have done （肯定已经…）

may/might have done (可能已经做了…) might not have done （不太可能已经…） should have done (本应该而没做…)

shouldn’t have done（本不应当做而做了…） needn’t have done（本没必要而做了…）

1. Why did you stay at a hotel when you were in New York? You ____could have stayed _____ with Barbara there.

2. The phone rang but I didn’t hear. I ____ must have been asleep _____ at that

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time.

3. –Do you think she saw you? --No, she was too far away. She __couldn’t have seen ___ me.

4. –I wonder why she didn’t say hello. Perhaps she didn’t see me. --That’s possible. She ___ might not have seen ___ you. 5. –Do you know where George is? I can’t find him anywhere. --I’m not sure. He ____ might have gone shopping___.

6. If I hadn’t slipped on the stairs, I ___ wouldn’t have broken____ my arm. 7. Why did you wash that shirt? It wasn’t dirty. You ___ needn’t have washed ___ it. 8. It was a great party last night. You ___ should have come___. Why didn’t you? 9. I’m feeling sick, for I have eaten a lot of chocolate. I _____ shouldn’t have eaten ____ too much chocolate.

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