动词填空。
1. John is still in hospital and the doctors will do all they can _________ (save) his life.
2. My brother _________ (educate) in the United States in 2008.
3. Smoking _________ (affect) people's health. You'd better give up smoking.
4. When I entered her room, she _________ (download) some information.
5. By studying hard and not _________ (give) up, you will succeed.
6. This is the best film that he _________ (see).
7. I didn't understand the problem until it _________ (explain) a third time.
8. He promised he _________ (treat) every student equally.
9. When he came to visit me, I _________ just _________ (go) out. So we had only a few words.
10. It is common that some people prefer _________ (sell) their old houses to buy new ones.