下列关于盐类水解的叙述中，错误的是[ ] A．盐类水解是中和反应的逆反应 B．盐

根据短文内容判断正T误F。

     Mr Black is an English teacher in a middle school. He teaches English. He often gets up early every

day, and he has breakfast at seven thirty in the morning. Then he goes to school. He works very hard

all day, and he also plays sports with his students. After school, he goes home at five in the afternoon. 

 He has dinner at six. After that he does his work in the room. He has a little cat, and he loves it very

much. He plays with it in the evening.

( )1. Mr White is an English teacher.                      

( )2. He teaches English in a primary school.              

( )3. He has breakfast at seven in the morning.            

( )4. He plays sports with his students.                    

( )5. Mr White has a little dog, and he likes it very much.

把下列句子按正确顺序排列。

( ) Whose dress is it?   

(     ) Thank you.   

(     ) It's my dress. It's paper.   

(     ) It's so beautiful.   

(     ) Look at my T-shirt! Isn't it cool?

在“探究凸透镜成像的规律”实验中

（1）实验前，先使烛焰、凸透镜和关屏在一条直线上，再调整他们的高度，调整的要求是 ______．

（2）实验后，小王同学未及时吹灭烛焰，一段时间后他发现，原来在屏中央的烛焰像移到了屏的边缘，那么．烛焰像移到了屏的 ______边缘（选填“上”、“下”、“左”或“右”），出现这一现象的原因是 ______．

受风化、地震、地质构造变动或施工等影响，在自重作用下，突然从悬崖、陡坡跌落下来的现象是指( )。

A．崩塌

B．断层

C．滑坡

D．地震

简述三级生产指挥系统。