根据中英文写出单词的适当形式。

1. On __________(下雨的) days, most people don't like to go out.

2. We lost ourselves in the __________(美丽) of Jiuzhaigou.

3. At 6 months old, Xi wang began to eat bamboo shoots and __________(叶子).

4. I have __________(少) money than Millie.

5. I study birds and __________(变化) in their numbers .