情态动词 can, may, must, need, should, shall, will, could, would

1.The bird can sing sweet songs.

2.Can I help you?

3.May I leave the table now? No, you may not.

4.Must I do my homework at once? No, you needn’t.

5.You should apologize to Mr Hopkins.

6.Shall we go by ourselves?

7.Could you help Linda with her lessons later?

情态动词的几种特殊用法：

must1. must + 动词原形： 表示说话人对现有状态的主观猜测；意思是“一定是”注意此结构不用在否定句中。Even the top students in our class can’t work out this problem, so it must be very difficult.

Susan’s parents have bought a large house with a swimming pool. It must be very expensive.

2. 用 must 开问的一般疑问句的肯定的回答只能是 must; 但否定的回答有两种：一定不行的用 mustn’t; 没有必要用 needn’t.

1.A: Must I finish my homework before I play video games, Mum?

B: I’m afraid you must.

2. A: Must I get up early tomorrow, Dad?

B: No, you needn’t. Tomorrow is Sunday.

3. 对用 May 开问的一般疑问句的肯定回答通常用 may; 但否定的回答也有两种；不可以的用 may not; 绝对不行的用 mustn’t.

1.A: May I have some chocolates now?

B: Yes, you may.

2. A: May I have some chocolates now?

B: No, you may not.

3. A: May I play football now?

B: No, you mustn’t.

can

1. Can 开问的句子，无论肯定还是否定，都用 can 来回答。

A: Can I play football now?

B: Yes, you can. No, you can’t.

2. 在征询对方许可的疑问句首， 可用 can 也可用may 开问

A: Can I come in? / May I come in ？

B: Yes, you can. / Yes, you may.

4. 用 Could 开问的句子不表示过去时， 只表示语气的委婉，答句或后面的宾语从句都从现在时范畴的时态考虑。

1. A: Could you help me with my lessons?

B: Of course I can.

2. Could you tell me if you have finished your work?

would

情态动词 would 主要表示”愿意“， 其次作为 will 的过去式使用。

1.Would you like some tea? Yes, please. / No, thanks.

2.Would you like to join us? Yes, I’d like to.

3.Would you like me to help you with your English?

Yes, please. / That’s very kind of you.

No, thanks. / No, thank you. I can do it myself.

1.Because there is no light in the room, he _____ be in. A. mustn't B. can't C. needn't D. dare not2.---May I smoke here? --- No, ________. A. you mustn't B. you may not C. you'd better not D. all the three answers3.---Could I use your pen? --- Certainly, you ______. A. will B. can C. may D. could 4. --- Must we finish the work today? --- No, you ______. You may leave some to tomorrow. A. can't B. mustn't C. don't D. needn't5. You _____ to the meeting this afternoon if you have something important to do. A. needn't to come B. don't need come C. don't need coming D. needn't come

B

A

B

D

D