问题 多项选择题

剂量效应和剂量反应关系的异同是()。

A.在环境流行病学研究中常以暴露剂量来取代这两个关系中剂量

B.在环境流行病学研究中不得以暴露剂量来取代这两个关系中剂量

C.这两个关系前者是表示群体的效应关系,后者表示个体的反应关系

D.这两个关系是一个概念

E.这两个关系前者是表示个体的效应关系,后者表示群体的反应关系

答案

参考答案:A, E

阅读理解

阅读理解。

     As one approaches some crossroads, one comes to a sign which says that drivers have to stop when

they come to the main road ahead. At other crossroads, drivers have to go slow, but they do not actually

have to stop (unless, of course, there is something coming along the main road); and at still others, they do not have either to stop or to go slow, because they are themselves on the main road.

    Mr. Williams, who was always a very careful driver, was driving home from work one evening when

he came to a crossroads. It had a "Slow" sign, so he slowed down when he came to the main road,

looked both ways to see that nothing was coming, and then drove across without stopping completely.

     At once he heard a police whistle, so he pulled in to the side of the road and stopped. A policeman

walked over to him with a notebook and pencil in his hand and said, "You didn't stop at the crossing."

"But the sign there doesn't say "Stop"," answered Mr. Williams. "It just says "Slow", and I did go slow."  

The policeman looked around him, and a look of surprise came over his face. Then he put his notebook

and pencil away, scratched his head and said, "Well, I'll be scolded. I am in the wrong street!"        

1. Which of the following statements is correct? ?

A. Stop signs can be found at every crossroads.

B. At crossroads with a "Slow" sign, drivers never have to stop.

C. At crossroads with a "Slow" sign, drivers have to stop and then go slow.

D. At some crossroads, drivers needn't stop or go slow.

2. What do you think the policeman would do in the end?

A. Fine Mr. Williams.                    

B. Take him to the police station.

C. Apologize to Mr. Williams.            

D. Give Mr. Williams his notebook and pencil.

3. Which might be the best title for this passage?

A. Signs at the crossroads              

B. A careful driver

C. A policeman and a driver            

D. Policeman in the wrong street

单项选择题 A1/A2型题