情态动词的肯定回答和否定回答

must和need相同:Yes,... must. No,... needn't/don't have to

may和can could相同:Yes,... may/can/could. No,... mustn't/...'d better not/can't.

shall:Yes,... can/may. No,... can't.

should:Yes,... should. No,... shouldn't.

will和would差不多:Yes,...do/will. No,...won't/thanks.

典型例题
1）---Could I borrow your dictionary?
---Yes, of course, you____.
A. might B. will C. can D. should
答案C.could表示委婉的语气，并不为时态。答语中of course，表示肯定的语气，允许某人做某事时，用can和 may来表达，不能用could或might。复习： will 与you连用，用来提出要求或下命令。should与you 连用，用来提出劝告。

2）---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
答案A。needn't 不必，不用。 wouldn't 将不, 不会的。 mustn't 禁止、不能。 shouldn't 不应该。本题为不需要，不必的意思，应用needn't。

3）---Don't forget to come to my birthday party tomorrow.
---______.
A. I