公路水运工程安全生产监督管理应当坚持的安全生产方针是( )A．统一监管 B．安全第

用所给词的适当形式填空。

1. Thank you very much for              (help) me so much.

2. When I             (walk) in the street, I             (meet) him.

3. Liu Hua             (buy) a grammer book yesterday.

4. His son             (study) English in England last year.

5. Can you finish             (do) your homework at 10?

6. They             (go) out for a walk if it doesn't rain.

7. He             (say) he will go to Beijing.

8. They             (do) their lesson this time yesterday.

9. Mr Smith wanted             (have) his holiday in London.

10. He             (not watch) TV every day.

在“观察水的沸腾”的实验中除了烧杯、铁架台、酒精灯、火柴、钟表外，主要器材还缺______．

离心泵装置是水泵与相配的电动机、管路及（）组成的系统。

当以路灯型安装形态固定时，一根灯安装2台AP，4副天线，各AP天线间应保持垂直大于（）且机箱位于两AP天线之间。

A、0.3米

B、1米

C、1.3米

D、2米