问题 单项选择题 A1型题

光化学烟雾的主要成分是()

A.颗粒物

B.紫外线

C.SO2

D.O3

E.PHA

答案

参考答案:D

解析:光化学烟雾是一种混合物,含有多种强刺激性气体。其中尤以O3的含量最高,约占85%以上,故D是正确答案。颗粒物、SO2和PHA不是光化学烟雾的成分。紫外线是产生光化学作用的光源,而不是成分。

阅读理解

阅读理解。

     A professor told his students to go into the city slum (贫民窟) to study the life of 200 boys.  He

asked them to write reports about each boy's life and future. Every one of the students wrote, "He

doesn't have any hope. "

    Twenty-five years later,  another professor read about the  earlier study.  He told his students to

find out what had happened to these boys. Of the 200 boys, 20 had moved away or died. Nobody

knew what had happened to them. They tried very hard and found the other 180 people.  Among

them 176 had become successful as doctors, teachers, and scientists.

    The professor was very surprised and decided to study it further.Luckily, all the men were living

near the place and he was able to ask each one, "What made you successful? "Each one answered

with feeling, "There was a teacher. "

    The teacher was still living there,  so the professor found her and asked the old woman what she

had used to pull those out of the slums,and change them into successful people.

    The teacher's eyes began to shine and she said with a sweet smile,"It's really very easy.  I loved

the boys. "

1. Why did the students go to the slums?      

A. To help the poor children.

B. To look for a good teacher.

C. To study the life of some young boys.

D. To become successful people.

2. Of the 200 boys, how many were known to be not successful?

A. 4.    

B. 20.    

C. 24.    

D. 176.                     

3. What changed the boys' life?

A. The professor's study.    

B. The teacher's love.

C. Their parents.            

D. The slums.

4. Why was the second professor surprised?

A. Because some boys had died.

B. L3ecause most of the boys lived a hard life.

C. Because a few boys didn't have hope.

D. Because the earlier reports were wrong.

5. Which of the following is NOT true?       

A. Some of the boys became doctors.

B. The second professor talked to the 180 people and their teacher.

C. The teacher sill remembered the boys.

D. The boys did't want to talk about their teacher.

问答题 简答题