用所给单词的适当形式填空。
1. I won't leave until it ____ (not) rain.
2. He often hears the boy____ (play) the guitar,
3. If you drink some tea before going to bed, you will be possibly____(wake) and can't
easily get to sleep again.
4. I felt ____(tire) after a long time of study.
5. It's important ____(keep) healthy.