选出适当的单词填空。

1. There are many _____________ (house, houses) in my village.

2. There are tall _____________ (building, buildings) in the city.

3. There is a _____________ (bridge, bridges) in the village.

4. There are some _____________ (river, rivers) in your village.

5. There are many _____________ (tree, trees) in my school.

传染性非典型肺炎防治工作应坚持的原则是（）

A.预防为主，防治结合，分级负责，依靠科学，依法管理

B.预防为主，及时隔离，依靠科学，防治结合，加强监督

C.有效预防，宣传教育，加强监测，防治结合，科学管理

D.预防控制，分级负责，依靠科学，防治结合，及时隔离

E.预防为主，及时控制，科学治疗，统一监测，防治结合