题目内容：

单词分类；请根据所给句子的意思，从下面的方框中选出可以填入句子中的单词，并将其字母标号填在答题卷相应的位置。

1.Do you know that scientists have           /           water on Mars?

2.We all like the music because it is very         /        .

3.He is a clever boy and he can play the         /          very well.

4.Tony’s father is a famous          /         .

5.You should smile when you like           or          .