1 . — Few of my fellows passed the politics quiz this time on campus.
— How come? It ________ tough.

A．should be

B．might be

C．must have been

D．would have been

3 . — That woman has been taking care of the two white tigers for 8 years.
—Oh, dear! She _____ a lot of difficulties!

A．could go through	B．might go through
C．might have gone through	D．must have gone through

6 . The students answered all the questions correctly. She ______ full preparations.

A．must make

B．should make

C．must have made

D．should have made

7 . —Why didn’t you come to Mike’s birthday party yesterday ?
—Well, I________, but I forgot it.

A．should

B．must

C．should have

D．must have

8 . 选词填空
1. —Must I finish the task right now?
—No，you ________ (don’t have to/mustn’t)
2. It’s so near. We ________ have taken a taxi.(shouldn’t/can’t)
3. You ________ have spent so much time playing computer games.(mustn’t/oughtn’t to)
4. ―Shall I leave the room so that you two can talk?
―No, you ________.(mustn’t/needn’t)
5. He ________ have missed the train; he arrived atthe train station two hours earlier.(can’t/mustn’t)
6. You ________ start at once if you want to catch the bus.(have to/ought to)
7. They ________ stay in the office last night because of the snowstorm.(had to/must)
8. We _______ have helped him; in that case, he would have been able to finish the work.(should/can)
9. He finished all the work himself; in fact, he ________ have asked his friends for help.(need/could)
10. Something terrible ________ have happened if Li Chang was not coming to eat in his restaurant as he always did.(have to/must)

9 . Something ________ have happened to Mary—She’s been crying all morning. (Possibility) (用适当的词填空)

10 . ________________ (肯定有人打开了笼子). The dog couldn’t have escaped on its own. (根据汉语提示完成句子)