9. I don't know ____ so many people are looking at him. (how, why)

8. I was really surprised at ______ I saw. (where, what)

7. We are talking about ______ we’ll go back tomorrow. (whether, if)

6. They don't know _______ to go or wait. (if, whether)

5. I really don't know ________ the bridge will be finished.(how long, how soon)

4. He always thinks ______ he can do better.(how, who)

3. She said _____ it wouldn't matter much.(that, if)

2. Do you know ______ else is going to be on duty today？(who, whom)

1. Jim told me ____ he didn't go fishing yesterday afternoon.(how, why)

30.(　 ) Do you know _____ they listened to yesterday evening?

A. what 　　B when　 　C why 　　D how