CanCan Could 能够 MayMay Might 或许 MustMust 必须 Ought to 应该 Shall Should 应该 Will Would 会

Common Modal Verbs:常见的情态动词：

P.S: Today we just learn three of them: can, may, must.

1. Modal verbs do not take “-s” in the third person. 第三人称后不需要加“ -s” 。

e.g. He can  speak Chinese.

2. 否定句 直接在情态动词后加 “ not”.

e.g. They may not come to the party.

3. Many modal verbs cannot be used in the past tenses or the future tenses.

许多情态动词不能用于过去时或者将来时。 e.g. She musted study very hard.

Modal verbs are special verbs which behave very differently from

normal verbs. 情态动词是特殊的动词，它们和其他单词很不一样！情态动词是特殊的动词，它们和其他单词很不一样！

x

Can (be able to)Can (be able to)

• “Can” 是最常用的一个情态动词。它能用来表示 能力、许可和可能性。

e.g. I can ride a horse.

Can I use your pen?

You cannot spell.

Can 的过去时 could /kud/

Using “can” in present and past

肯定句1. 现在时 2. 过去时

否定句1. 现在时 2. 过去时

1. I can speak Chinese. 1. I can’t speak Chinese.

2. I could speak Chinese when I was a kid.

2. I couldn’t speak Chinese when I was a kid.

Ask and answer

Can Kitty spell? Yes, she can.

____ Derek _______? _____________

_____ Kitty ______? ______________

____ Kitty _________? _____________

Can multiply

CanCan

No, he can’t.

subtractYes, she can. Yes, she can.

add

• “may” 常被用来表达可能性，也可以表示请求。

表示请求： May I use your bathroom? 表示可能性 ： I may go shopping in the after

noon.

may 的过去时 mightHe might be our new teacher.PS ： might 也可以表示推测，可能性比 may 小 ,

语气更婉转。

may (perhaps) 也许 , 可能

Using “may” in present, future and past

Positive forms1. present 2. past

Negative forms1.present 2. past

1. Jack may be angry. I can’t tell.

1. Jack may not be angry. Maybe he is tired.

3. Jack might be at home.

3. Jack might not be at home.

“Must” 用来表示确定的意思，表示必须，一定 。

必须： You must buy a ticket.

一定 ： He must be our new teacher.

must not 表示禁止You must not park here.

Must (have to)

What do the signs mean? Do you know?

You must not cycle.

You must be careful. You must turn left.

You must not enter.

You must pay ten yuan. You must keep silent.

You must not turn right.You must not smoke.

★ 情态动词情态动词不能单独作谓语动词，后接其它动词原形动词原形做谓语，没有人称和数的变化。1.表示能够或不能做某事用 can 或

can’t; A bird can fly . Fish can’t live without water.2. 告诉人们必须或禁止做某事用 mus

t 或 mustn’t; You must hand in your homework at o

nce. You mustn’t talk loudly in public.

3. 表示请求或允许做某事 may 或 can; May I come in ? Can I open the door ?

4. 情态动词的疑问句：把 can may must 置于句首。Can you play the guitar?

May I come in?

Must I finish the work today?

Yes ，… .can.No,….can’t

Yes ，… .may./SureNo,…may not / can’t.

Yes ，… .must.No,….needn’t.

★★★Notes :

1 、 can 和 be able to 的区别 : be able to 有 人称数和时态的变化。 I can come tomorrow . He was able to help the old lady. I will be able to come tomorrow.

2 、在回答 must 的疑问句时，否定回答常用 needn’t 或 don’t have to 表示不必，而不用 mustn’t 。 Must we stay here ? No, you needn’t . ( No, you don’t have to .)

★★★Notes :

3 、 May……? 的回答可以有下列方式：•Yes, of course.•Yes, please.•Sure.•No, you must not.•No, you can’t.

Do exercise about modal verbs1 John____ come to see us tonight, but he

isn’t very sure yet. A. may B. can

C. has to D. must

2 They _____ do well in the exam. A. can be able to B. be able to

C. can able to D. are able to

3 -May I take this book out? -No, you_______.

A. can’t B. may not C. needn’t D. aren’t

4 You_____ go and see a doctor at once because you’ve got a fever. A. can B. must C. dare D. would

5 -Can you speak Japanese? -No, I_______. A. mustn’t B. can’t C. needn’t D. may not

6 Must I finish the work today? No, you __.

A. don’t B. won’t C. needn’t D. mustn’t

7 You _____ talk loudly in the library.

A. don’t B. mustn’t

C. needn’t D. don’t have to

8 - You must come here at six tomorrow morning. -Sorry, I ____ be here so early. A. need B. can C. must D. can’t

9 After a long walk, the old man____ be tired now. A. must B. has to C. need D. can

Ⅰ. 用适当的情态动词填空：。

1.I can play football. __________you swim?

2.Don’t worry. You ________ return me this book tomorrow.

3.My grandma is ill. You _______ talk so loudly here .

4.I can’t play with you. I __________finish my homework first.

5.I__________ get up early tomorrow. because I have a meeting.

6.______________you please open the window?

Can

may

can’t

must

must

Can

9. Nobody ___________live without air.10._________he speak Chinese ?Yes ,a little.11. The book _________ be returned before Saturday.12.__________I come in ?Yes ,please.13. You ________give up smoking at once. It’s bad for your health.14. Excuse me ._________I ask you a question?15. __________you tell me where the station is ?16. _______ I finish the work now ?No, you _________. You _______ do it this evening.17. May I use your dictionary ? Sorry , you _________. I am using it now .18. Look at the ground .It’s very wet .It _______ have rained last night.

can Can

mustMay

must

May Can

Must

needn’t can can’t

must