【典型例题】

1. Peter ___come with us tonight, but he isn’t very sure yet.
　 A. must　　B. may　 C. can　 D. will 
答案B. 表可能性只能用may。此句意可从后半句推出。

2. ——-Shall we go skating or stay at home?——-Which ___ do?
　 A. do you rather　　B. would you rather　 C. will you rather　 D. should you rather
答案B。本题考查情态动词rather的用法，would rather +do sth. 意为“宁愿”，本题为疑问句，would 提前，所以选B。

3. ——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。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。

4. ——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。

5. ——Don’t forget to come to my birthday party tomorrow. ——______. 
　A. I don’t　 B. 　I won’t　 C. I can’t　D. I haven’t 
答案B. will既可当作情态动词，表请求、建议、也可作为实义动词表“意愿、意志、决心”，本题表示决心，选B。

6. Tom ought not to ___ me your secret, but he meant no harm.
　 A. have told　B. tell　C. be telling　D. having told
答案A.由于后句为过去时，告诉秘密的动作又发生在其前面，此地应用过去完成时，但它在情态动词 ought to 后，所以用have told。

练习

1. --Mary, ____ you speak Chinese?　-- Yes, only a little.
A. may　　　B. can　　　C. will　　　D. could

2. --Must I do the work now?　-- No, you ____. You can do it later.
A. can't　　　B. mustn't　　C. needn’t　　D. shouldn’t

3. -- I can't stop smoking, doctor.　-- For your health, I'm afraid you ____.
A. may　　　B. need　　　 C. must　　　D. can

4. -- Whose book is it?　-- It ____ be Bob's sister's. She is only a baby.
A. must　　　B. might　　　C. can't　　　 D. mustn't

5. -- Jill looks so painful, there ____ be something wrong with her.
-- Oh, dear! We'd better take her to the hospital at once.
A. can　　　B. should　　　C. would　　　D. must

6. -- May I try on the jeans?　-- Yes, you ___.
A. should　　　B. can　　　C. must　　　D. need

7. -- Are you going to Beijing by air?
-- It's fast but a litter expensive. So I am not sure. I __
A. should　　B. may　　C. must　　D. will

8. -- Could I borrow your dictionary?　-- Of course you ____.
A. can　　　B. must　　　C. should　　　D. will

9. --Don't forget to come to my birthday party tomorrow.　--No,____.
A. I don't　　 B. I won't　　C. I can't　　D. I haven’t

10. -- Must I tidy the room now?　　
-- No, you ____. You ____ do it after breakfast.
A. mustn't, cam　B. needn't, may　C. don't, have to　 D. needn’t, must