如图所示，斜面位于水平面上，一小物块自斜面顶端沿斜面下滑. 已知各接触面均光滑，

某机电安装工程公司承担了一座36层高楼的防雷安装任务。为确保人身安全，安装工程公司派两名精通机电专业的技术人员、两名技术人员随同施工队一起参加工作。经多次安装检查无误后，项目才正式完成使用。

三相四线制供电系统，配电变压器的中性点一般是直接接地，称为( )。

A．保护接地

B．工作接地

C．重复接地

D．接零

阅读理解

     Kate’s bedroom is big. A TV set is in the room. The TV set is on the table. Some red flowers (花)

are on it, too. We can see a nice picture on the wall. We can see a hat and some books on her bed.

Her shoes are under the bed. A desk is near the window. On the desk is a clock. It’s time to go to

school (该上学了). Where’s Kate’s bag? Oh, it’s on the chair. Kate is putting on (穿上) her shoes.

1. We can see ________ on the table.

A. a TV set and some red flowers

B. some red flowers    

C. a TV set  

2. Where’s Kate’s hat? It’s __________.

A. on the chair        

B. on the bed        

C. under the chair      

3. Where’s Kate’s bag? It’s _________.

A. on the chair        

B. under the bed        

C. on the wall

4. How many pictures are there in the bedroom?

A. Three.      

B. Two.        

C. One.    

5. What’s the Chinese meaning for the word “shoes” ? It’s         . 

A. 拖鞋      

B. 袜子    

C. 鞋子

根据树木对土壤肥力的要求不同可分为（）、瘠土树种，中性树种三类。

校正、改善线路纵断面和平面不属于普通线路换轨大修主要内容。

简述拖擦地面操作步骤。