用所给词的适当形式填空。
1. I can't choose which pair of jeans _______ (buy). They both look good on me.
2. Why do you look _______ (sleep)?
3. Everyone needs to have at least eight _______ (hour) sleep a night.
4. But we do think that our son needs to be _______ (real).
5. My parents have always taught me the _______ (important) of working hard.
6. Children shouldn't be allowed _______ loudly in class. (shout).
7. He should stop _______ (wear) that silly sweater.
8. It's probably a good idea for parents _______ (allow) teenagers to study in groups.
9. Do you think children should _______ (allow) to play computer games..
10. At our school, we sometimes have a special day _______ (help) others.