根据句意写出所给单词的正确形式。
1. Look! One of the children (swim) in the lake.
2. Lily is much __ (health) than her sister.
3. They ____ (fly) to the UK, didn't they?
4. Is ____ (eat) too much good or bad for your body?
5. Mr. Lee ___ _ (give) us a talk on the history of China tomorrow, isn't he?