用所给单词的适当形式填空。

1. They are playing games. They are very ______ (relax).

2. There are many different kinds of ______ (scarf) in the mall.

3. What a ______ (sun) day it is!

4. The man enjoys ______ (lie) on the beach.

5. I usually sleep when it's ______ (rain).

下列统计分组中，分组标志采用数量标志的是()。

A.人口按年龄分组

B.企业按职工人数分组

C.儿童按身高分组

D.职工按文化程度分组