细胞中下列结构名词所对应的相应功能，正确的是（ ） A．细胞膜--控制物质进出

阅读理解。

      I am an English girl. My name is Mary. I'm twelve. My dad and mom are English teachers.

I have a brother(哥哥). His name is Tom and he is thirteen years old. We are in China now.

We are in Beijing No. 4 Junior High School. Tom is in Class 4, Grade 7 and I am in Class 9,

Grade 7. I have a dog. My dog looks strong. It has a big mouth and two big black ears. We

have many(许多) Chinese friends here. They are good.

根据短文内容,判断正(T)误(F).

( )1. Mary comes from the U.S.A.

(     )2. Mary and Tom are in the same class, but they are in different grades.

(     )3. Mary's dog's mouth and ears are big.

(     )4. The dog's ears are white.

(     )5. Tom and Mary have many friends in China.

—What do you think of the furniture on exhibition?  

—Well, great! But I don't think much of ______ you bought.   [ ]

A. the one      

B. it        

C. which        

D. that

公文的基本组成部分有( )

A．标题

B．文头

C．正文

D．主题词

社会惰化的研究指出，随着群体规模( )，个体付出的努力( )。

A．减小 增加
B．增加 减小
C．减小 减小
D．增加 增加

汽动给水泵若要隔绝，则给水泵前置泵必须停用。