题目内容：

根据句意选词并用其适当形式填空。

 

1.Of all the ________， I think Mickey Mouse is the prettiest.

2.We should take action to kept water from ________.

3.It is a new kind of computer. Please use it ________.

4.---You can improve your __________ of grammar by playing this game.

---That’s very nice of you.

5.The little boy often looks sad because he misses his _______ lovely pet very much.