人教版高中英语必修三Unit1 情态动词精品学案(精修版)

人教版英语精品资料（精修版）
情态动词精品学案
一、情态助动词的词法和句法特征：
1. 情态动词只能接不带to的不定式：
We used to grow beautiful roses.
I asked if he would come and repair my television set.
2. 情态助动词用于第三人称单数现在时的时候，没有词形变化，即其词尾无-s形式：
She dare not say what she thinks.
3. 情态动词没有非限定形式，即没有不定式、-ing分词和-ed分词形式：
Still, she needn’t have run away.
二.、情态助动词的意义和用法
1. can和could的用法
1). 表示能力或客观可能性，还可以表示请求和允许。

如：
Can you finish this work tonight?
Man cannot live without air.
— Can I go now? — Yes, you can.
①could也可表示请求，预期委婉，主要用于疑问句，不可用于肯定句，答语应用can（即could不能用于现在时态的简略答语中）。

如：
Could I come to see you tomorrow?
Yes, you can. （否定答语可用No, I’m afraid not.）
②can表示能力时，还可用be able to代替。

如：
I’ll not be able to come this afternoon.
2)．表示惊异、怀疑、不相信的态度。

（主要用在否定句、疑问句或感叹句中）Can this be true?
How can you be so careless!
This cannot be done by him.
3)．“can(could) + have + 过去分词”的疑问或否定形式表示对过去发生的行为怀疑或不肯定。

如：
He cannot have been to that town.
Can he have got the book?
2. may和might的用法
1)．表示许可。

表示请求、允许时，might比many的语气更委婉一些，否定回答时要用mustn’t 表示“不可以”、“禁止”、“阻止”之意。

如：
You may drive the car.
— Might I use your pen? —No, you mustn’t.
用May I ... 征询对方许可在文体上比较正式，在口气上比较客气。

在日常口语中，用Can I ... 征询对方意见在现代口语中更为常见。

2)．用于祈使句中表示祝愿。

如：
May you succeed!
3)．表示推测、可能（疑问句不能用于此意）。

He may be very busy now.
4)．“may(might) + have + 过去分词”表示对过去发生的行为的推测。

如：
He may not have finished the work.
3. must和have to的用法
1)．表示必须、必要。

如：
You must come in time.
回答must引出的问句时，如果是否定的回答，不能用mustn’t，而要用needn’t或don’t have to。

— Must we hand in our exercise books today?
—Yes, you must. (No, you don’t have to.)
2)．“must be + 表语”的结构表示推测，它的否定或疑问式用can代替must。

This must be your pen.
3)．“must + have + 过去分词”的结构常用在肯定句中，表示对过去发生的行为的推测。

它的否定或疑问式用can代替must。

He must have been to Shanghai.
4)． have to的含义与must相似，两者往往可以互换使用，但have to有各种形式，
随have的变化而定。

must与have to有下列几点不同：
① must表示的是说话人的主观看法，而have to则往往强调客观需要。

如：
The play is not interesting. I really must go now.
I had to work when I was your age.
② must一般只表现在，have则有更多的时态形式。

③二者的否定意义不大相同。

如：
You mustn’t go. 你可不要去。

You don’t have to go. 你不必去。

④询问对方的意愿时应用must。

如：
Must I clean all the room?
4. dare和need的用法
1)． need表示“需要”或“必须”，作情态动词时，仅用于否定句或疑问句中，在肯定句中一般用must, have to, ought to,或should代替。

如：
You needn’t come so early.
— Need I finish the work today?
— Yes, you must.
needn’t + 不定式的完成式“表示本来不必做某事而实际上做了某事”。

如：
You needn’t have waited for me.
2)． Dare作情态动词时，主要用于疑问句、否定句和条件从句中，一般不用在肯定句中。

如：
How dare you say I’m unfair.
He daren’t speak English before such a crowd, dare he?
3)． Dare和need常用作实义动词，有时态、人称和数的变化，所不同的是，作实义动词时，在肯定句中，dare后面通常接带to的不定式，在否定和疑问句中，dare后面可接带to或不带to的不定式。

如：
I dare to swim across this river.
He does not dare (to) answer.
Don’t you dare (to) touch it!
I wondered he dare (to) say that.
He needs to finish it this evening.
5. shall和should的用法
1)． Shall用于第一人称，表示征求对方的意愿。

如：
What shall we do this evening?
2)． Shall用于第一、第三人称疑问句中，表示说话人征求对方的意见或向对方请示。

如：
Shall we begin our lesson?
When shall he be able to leave the hospital?
3)． Shall用于第二、第三人称，表示说话人给对方命令、警告、允诺或威胁。

如：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）
4)． Should表示劝告、建议、命令，其同义词是ought to；在疑问句中，通常用should代替ought to。

如：
You should go to class right away.
Should I open the window?
Should的含义较多，用法较活，现介绍三种其特殊用法。

请看下面的句子：
① I should think it would be better to try it again. 我倒是认为最好再试一试。

② You are mistaken, I should say. 依我看，你是搞错了。

③ I should advise you not to do that. 我倒是劝你别这样做。

④ This is something I should have liked to ask you. 这是我本来想问你的。

从以上例句可以看出：情态动词should用于第一人称时可以表示说话人的一种谦逊、客气、委婉的语气。

Should还可以用在if引导的条件从句，表示一件事听起来可能性很小，但也不是完全没有可能。

相当于“万一”的意思。

从句谓语由should加动词原形构成，主句谓语却不一定用虚拟语气。

如：
⑤ Ask her to ring me up if you should see her. 你万一见到她，请让她给我打个电话。

⑥ If you should change your mind, please let us know. 万一你改变主意，请通知我们。

⑦ Should I (If I should) be free tomorrow I will come. 万一我明天有时间，我就来。

此外，Why(or How) + should结构表示说话人对某事不能理解，感到意外、惊异等意思。

意为“竟会”。

如：
⑧ Why should you be so late today? 你几天怎么来得这么晚？
⑨— Where is Betty living? —贝蒂住在哪里？
— How should I know? —我怎么会知道呢？
⑩I 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)．“should + have + 过去分词”结构一般表示义务，表示应该做到而实际上没有做到，并包含一种埋怨、责备的口气。

如：
She should have finished it.
I should have helped her, but I never could.
You should have started earlier.
6. will和would的用法
1)．表示请求、建议等，would比will委婉客气。

如：
Would you pass me the book?
2)．表示意志、愿望和决心。

如：
I will never do that again.
They asked if we would do that again.
3)．用“will be”和“will(would) + have + 过去分词”的结构表示推测，主要用于第
二、三人称。

前者表示对目前情况的推测，后者表示对已经完成的动作或事态的推测。

如：
This will be the book you want.
He will have arrived by now.
The guests would have arrived by that time.
I thought you would have finished this by now.
4)． Would可表示过去反复发生的动作或某中倾向。

Would表过去习惯时比used to 正式，并没有“现已无此习惯”的含义。

如：
The wound would not heal.
During the vacation he would visit me every week.
5)．表料想或猜想。

如：
It would be about ten when he left home.
What would she be doing there?
I thought he would have told you all about it.
7. ought to的用法
1)． Ought to表示应该。

如：
You ought to take care of him.
2)．表示推测。

注意与must表示推测时的区别：
He must be at home by now. （断定他已到家）
He ought to be home by now. （不十分肯定）
This is where the oil must be. （比较直率）
This is where the oil ought to be. （比较含蓄）
3)．“ought t o + have + 过去分词”表示过去应做某事而实际未做。

如：
You ought to have asked him (but you didn’t).
这时，ought to和should可以互相换用。

在美国英语中，ought to用于否定句和疑问句时，to可以省略。

如：
Ought you smoke so much?
You oughtn’t smoke so much.
8. used to，had better，would rather的用法
1)． Used to表示过去的习惯动作或状态，现在已不存在，在间接引语中，其形式可不变。

如：
He told us he used to play football when he was young.
在疑问句、否定句、否定疑问句或强调句中，可有两种形式：
疑问句 Did you use to go to the same school as your brother?
Used you to go to the same school as your brother?
否定句I usedn’t to go there.
I didn’t us e to go there.
Usedn’t 亦可拼作usen’t，但发音皆为[ju:znt]。

否定疑问句Usen’t you to be interested in the theatre?
Didn’t you use to be interested in the theatre?
强调句 I certainly used to smoke, but it was a long time ago.
I certainly did use to smoke, but it was a long time ago.
其反意疑问句或简略回答中，也有两种形式：
She used to be very fat, didn’t she? （正式）/ use(d)n’t she? （口语）
Did you use to play chess? Yes, I did.
Used you to get up early in the morning? Yes, I did. (Yes, I used to.)
2)． Had better意为“最好”，后接不带to的不定式。

如：
— We had better go now.
—Yes, we had (we’d better / we had better).
Hadn’t we better stop now? (Had we better not stop now?)
I think I’d better be going. （用于进行时态，表“最好立即”）
You had better have done that. （用于完成时态，表未完成动作）
①had best与had better同意，但较少用。

②You had better … 用于同辈或小辈，对长辈不可用。

3)． Would rather意为“宁愿”，表选择，后接不带to的不定式。

如：
I’d rather not say anything.
Would you rather work on a farm?
—Wouldn’t you rather stay here?
—No, I would not. I’d rather go there.
由于would rather表选择，因而后可接than。

如：
I would rather work on a farm than in a factory.
I would rather watch TV than go to see the film.
I would rather lose a dozen cherry trees than that you should tell me one lie.
I’d rather you didn’t talk about this to anyone. （句中的’d rather不是情态动词，would 在此是表愿望的实义动词）
三、强化练习
选择填空
1. 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
2. Where is my pen? I _____ it.
A. might lose
B. would have lost
C. should have lost
D. must have lost
3. I wish I _____ you yesterday.
A. seen
B. did see
C. had seen
D. were to see
4. I didn’t hear the phone. I _____ asleep.
A. must be
B. must have been
C. should be
D. should have been
5. If my lawyer _____ here last Saturday, he _____ me from going.
A. had been; would have prevented
B. had been; would prevent
C. were; would prevent
D. were; would have prevented
6. He _____ you more help, even though he was very busy.
A. might have given
B. might have
C. may have given
D. may give
7. If it _____ for the snow, we _____ the mountain yesterday.
A. were not; could have climbed
B. were not; could climb
C. had not been; could have climbed
D. had not been; could climb
8. Without electricity human life _____ quite difficult today.
A. is
B. will be
C. would have been
D. would be
9. A computer _____ think for itself, it must be told what to do.
A. can’t
B. couldn’t
C. may not
D. might not
10. Jenny _____ have kept her word. I wonder why she changed her mind.
A. must
B. should
C. need
D. would
11. We _____ last night, but we went to the concert instead.
A. must have studied
B. might study
C. should have studied
D. would study
12. — Could I borrow your dictionary?
— Yes, of course you _____.
A. might
B. will
C. can
D. should
13. Tom ought not to _____ me your secret, but he meant no harm.
A. have told
B. tell
C. be telling
D. having told
14. — If he _____, he _____ that food.
— Luckily he was sent to the hospital immediately.
A. was warned; would not take
B. had been warned; would not have taken
C. would be warned; had not taken
D. would have been warned; had not taken
15. Peter _____ come wi th us tonight, but he isn’t very sure yet.
A. must
B. may
C. can
D. will
16. I told Sally how to get here, but perhaps I _____ for her.
A. had to write it out
B. must have written it out
C. should have written it out
D. ought to write it out
17. I didn’t see your sister at the meeting. If she _____, she would have met my brother.
A. has come
B. did come
C. came
D. had come
18. — Shall I tell John about it?
— No, you _____. I’ve told him already.
A. needn’t
B. wouldn’t
C. mustn’t
D. shouldn’t
19. When a pencil is partly in a glass of water, it looks as if it _____.
A. breaks
B. has broken
C. were broken
D. had been broken
20. It’s nearly seven o’clock. Jack _____ be here at any moment.
A. must
B. need
C. should
D. can
21.— There were already five people in the car but they managed to take me as well. — It _____ a comfortable journey.
A. can’t be
B. shouldn’t be
C. mustn’t have been
D. couldn’t have been
22. 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
23. The fire spread through the hotel very quickly but everyone _____ get out.
A. had to
B. would
C. could
D. was able to
24. — 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
25. — 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
26. — 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
27. —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
28. — Write to me when you get home.
— _____.
A. I must
B. I should
C. I will
D. I can
29. I was really anxious about you, you _____ home without a word.
A. mustn’t leave
B. shouldn’t have left
C. couldn’t have left
D. needn’t leave
30. — Is John coming by train?
— He should, but he _____ not. He likes driving his car.
A. must
B. can
C. need
D. may
答案与解析：
1．C 从原题中You can keep it till next week if you like这一信息句可知，“你不必现在还”。

2．D 从原题中Where is my pen?这一信息句可告诉考生，“笔丢了”，丢的动作是过去发生的。

因此用must + have done表示对过去事实的肯定猜测。

3．C 原题中的yesterday这一信息词告诉考生，在wish后的宾语从句中，用过去完成时，表示与过去事实相反的愿望。

4．B 从原题中的I didn’t hear the phone.这一信息可以判断出，用must have done 表示过去事实的准确的肯定猜测。

5．A 从原题中last Saturday这一信息词可知，条件句中用表示与过去事实相反的过去完成时，主句用would + have done。

6．A might have + 过去分词，在次是虚拟语气，表示“本来可以给你更多的帮助”，而事实则是帮助较少。

7．C 从原题中的yesterday这一信息词暗示考生，该句应选用与过去事实相反的过去完成时，If it had not been for … “要不是因为……”。

8．D 原题中的Without electricity相当于一个条件句：If there were no electricity,故主句用human life would be quite difficult today.
9．A can可以表示一种客观上的能力，本句can’t，表示“不能，不会”。

10．B 从原题总的“I wonder why she changed her mind”“我不知道为何他改变了主意了。

”这句话告诉考生Janny没有守诺言。

因此，用should + have done，表示“过去本应该做某事，而实际上没有做”。

11．C 可参看10题。

意思是：“昨晚本应该学习，但是却去听音乐会了。

”12．C 原题中的could不是过去时，而表示一种委婉、客气的礼貌用语。

因此用could提问时，用can回答。

同样用would，might提问，用will和may回答。

[注意]①— Would you rather do such a thing? — Yes, I would.
②— Would you like some tea? — Yes, I would.
这两个对话中的would rather，would like是惯用法，故不能用will来回答。

因为
在这两个句型中，will不能去替换would。

13．A 可参看10、15题。

该句意思是：“汤姆本来不该告诉我你的秘密，但他没有伤害你的意思。

”ought not to have done = shouldn’t have done
14．B 从答语中的Luckily he was sent to the hospital immediately这一信息句可提示考生，条件句应填表示与过去事实相反的时态。

15．B 从原题中的but he isn’t very sure yet这一信息句可暗示考生，Peter当晚来的可能性不大。

A是“准来，肯定来”，D是“将要来”。

16．C 可参看10、11、13题。

“本应该”而事实上没有……
17．D 从原题中I didn’t see your sister at the meeting和后文she would have met my brother这两个信息句可知，if条件句中应填与过去事实相反的过去完成时。

可参看6、7、14题。

18．A 你不必告诉他。

因为I’ve told him already这一信息句已暗示考生了。

19．C 当as if引导虚拟语气的句子是，如果主句与从句中的谓语词所表达的动作同时发生时，as if后接一般过去时。

例如：He walked as if he were lame.如果从句中的谓语动作发生个在主句谓语动作之前，则用过去完成时。

例如：He talked as if he had known the secret.不论主句中的谓语是现在时还是过去时。

20．C 只要考生抓住nearly一词和后文at any moment（随时的意思）这两个信息词语，就能很快选出C项，表示逻辑推测，意思是“快七点钟了，杰克一会儿就该到了。

”
21．D 根据句意，是对过去情况的推测。

“当时决不可能是一次舒服的乘车。

”must 表示对过去的推测只能用于肯定句。

22．B mustn’t表示“禁止”；may表示“有可能”。

句子的意思是：“你不可以玩刀，可能会伤你自己。

”
23．D 该题在考考生could与was able to之间的区别。

Was able to表示在困难的情况下，经过一番周折而“能……”，并且成功地做了。

24．B 该题考查情态动词should表推测的用法。

Can和might都可以表示可能性，用might则语气更加不肯定。

Need表示“需要”、“必需”。

Should可以表示推测，结合实际，合乎逻辑，意为“应当”、“该”。

根据第一个说话者说的I need them tomorrow afternoon的语境，可以确定正确答案为B。

25．A 该题在考查“情态动词+不定式的完成式”的用法，从会话的语境看，空白处应填“could + have +过去分词”表示过去本来能做到的事而事实上没有做到。

26．B 该题考查表示请求的英语口语，用will来向第二人称提问的疑问结构，是表达一种意愿和请求，是以疑问的形式来表达较为婉转的祈使语气，意思是“请你……，好吗？”，对于这种问句的肯定答语可用Sure! Certainly! Yes, of course. I’d be glad to等；否定回答通常是I’m sorry, I can’t. No, I’m afraid I can’t. I’m sorry, but … I ‘d like to, but …等。

27．D might表示“可能性”。

28．C 意思是“我会的”。

对祈使句的肯定回答。

29．B shouldn’t have done为本来不该做某事，而事实上做了。

30．D 用may not可表示“可能不”。

而can not则表示断然的否定推测“不可能”。

A，C意思不符。