根据句意，写出括号内所给单词的适当形式
1. After drinking the cup of coffee, he felt even _________. (sleep)
2. Look, the children are trying to catch _________ (butterfly) on the flowers.
3. I have got toothache, so I must go to the ______________. (dentist)
4. We think more public activities will help change his ____________ life. (active)
