Read and write. (用所给单词的适当形式填空)

1. It's _____ for little children to play by the river by themselves. (danger)

2. — Who is _____, Tom or John? (clever)

    — Oh, it's hard to say.

3. The Space Museum is a very _____ place. (interest)

4. Guangzhou is in the _____ of China. (southern)

5. There are some new _____ on the desk. (photo)

诊断真性红细胞增多症的女性患者，其血红蛋白要求大于（）

A.160g／L

B.170g／L

C.180g／L

D.190g／L

E.200g／L