问题 选择题

下列与汽车有关的说法正确的是(  )

A.所用燃料是汽油,它是一种可再生能源

B.加油时,能闻到汽油是扩散现象

C.汽油机在做功冲程中,机械能转化为内能

D.急刹车时,车胎表面温度升高是由于热传递造成的

答案

A、汽油是从石油中经过提炼产生的,属于不可再生能源.错误.

B、汽油分子运动到空气中,所以人们可以闻到.正确.

C、做功冲程中,内能转化为机械能.错误.

D、刹车时,刹车片对车轮摩擦,通过做功的方式增大了物体的内能,使温度升高.错误.

故选B.

阅读理解

阅读理解

       One evening two young men were walking in the street together. They tried to find a chance to steal

something. The clock struck twelve. Most of the people went to bed. Quickly they came to a house and

it seemed that everyone in the house had fallen asleep. Standing at the front gate , one said in English to

the other in a low voice ,"You wait here. I'll go around to the back door and then get into the house."

Suddenly out of the house ran a dog, barking at them. The two men were very frightened and ran away

as fast as they could. Finally, they stopped at a lonely place. The man said breathlessly, "It's too bad. I

hadn't expected that the dog could understand English."1.Why did the two men walk in the street one

evening ?

1. Why did the two men walk in the street one evening ?

A. they couldn't fall asleep  

B. they wanted to steal something

C. they would like to take a walk  

D. they went to visit their friends

2. "One said in English to the other in a low voice." From this sentence we know ____.

A. he didn't know English  

B. he liked speaking English quietly    

C. he couldn't speak loud  

D. he was afraid of waking up others

3. The dog ran out of the house and barked at them only because _______.

A. it understood English

B. it knew them  

C. it found someone outside  

D. Both B and C

4. At last the two young men _______

A. stole nothing    

B. stole something expensive

C. were bitten by the dog

D. were bitten by the police

5. What did the owners do while the dog was barking ?

A. They stopped it          

B. They got up quickly

C. They shouted for help        

D. The story didn't tell us

填空题