1 . He ________ have finished writing the paper. He hadn’t written a single word when I left him fifty minutes ago. (用适当的词填空)

2 . 据说他们是从大陆游到那个岛的，但他们不可能做到，因为中间的海洋太宽了。
It’s said that they have swum to the island from the continent, but they ________________ it because the ocean in between is too wide.

3 . You ________ have seen Mary at the meeting this morning, because she left for Beijing yesterday. (用适当的词填空)

5 . 彼得是一个诚实的孩子，因此他不可能拿走抽屉里的钱。
Peter is an honest boy, so he________ the money in the drawer.

6 . She ________have participated in the activity, for she was doing paperwork in the office then. (用适当的词填空)

7 . I didn’t see her in the meeting room this morning. She __________ not have spoken at the meeting. (用适当的词填空)

8 . Why are your eyes so red? You _________（不可能睡好）last night. (根据汉语提示完成句子)

9 . —I saw Lily in the teacher’s office just now.
—You _________ her, she has gone back home.

A．must not see

B．mustn’t have seen

C．can’t have seen

D．couldn’t see