在砖木结构建筑屋顶灭火时，要加强防滑措施以免坠落受伤。（）

阅读理解。

     The children often play football in the garden and sometimes break (打破) Mr Black's windows. One

afternoon Mr Black is at home and reads a book. In a minute he closes his eyes and goes tosleep. At

that time a little boy knocks at the door. Mr. Black opens the door and asks, "Do you break my window

again (再一次)?" 

     "Oh , no" says the boy, "Your window is open this time and our football is in your room. May I get

it please?"

1. The children often play football _______ .

A. in the street (街道)

B. in the park

C. in the zoo(动物园)

D. in the garden

2. Sometimes the children break _______ windows .

A. Mrs White

B. Mrs Black's

C. Mr Black's

D. Mr White's

3. Who knocks at Mr Black's door?

A. A girl

B. A boy

C. A man

D. A woman

4. The children's football is _______ Mr Black's room .

A. in

B. on

C. behind

D. near

5. Do the children break Mr Black's window again ?

A. Yes , they do .

B. No , they don't .

C. Yes , we do .

D. No , we don't

TJWX-2000型微机监测系统监测绝缘值不对时应如何处理？

薄利多销定价法是属于（）。

A、需求差异定价法

B、反向定价法

C、竞争导向定价法

D、顾客差异定价法

下列关于输水隧洞的汽蚀产生的原因分析正确的有（）。

A.输水洞进口形状不良

B.洞壁不平整

C.门槽尺寸不当

D.输水隧洞截面太大