问题 单项选择题

中国药典(2000年版)规定检查纯化水中氯化物、硫酸盐与钙盐的方法如下:取本品,分置3支试管中,每管各5ml。第1管中加硝酸5滴与硝酸银试液lml;第2管中加氯化钡试液2ml;第3管中加草酸铵试液2ml,均不得发生浑浊。该检查方法应属于

A.灵敏度法

B.对照法

C.沉淀反应

D.浊度法

E.限量法

答案

参考答案:A

阅读理解

阅读短文,回答问题。

     Some things can carry messages, for example, a sign at the bus stop helps you to know which bus to

take. Signs on the door tell you where to go in or out. Have you ever noticed that there are a lot of signs

around you and that you receive messages from them all the time?

     People can communicate on many other ways. An artist can use his drawing to tell about beautiful

mountains, about the blue sea and many other things. Books are written to tell you about all the wonderful

things in the world and also about people and their ideas.

     Books, magazines, TVs, radios and films all help us to communicate with others. They all help us to

know what is going on in the world and what other people are thinking about.

1. What can help you if you want to know which bus to take?

                                                                                                       

2. What do the signs on the door do? 

                                                                                                       

3. People can communicate in many other ways, can't they?

                                                                                                       

4. What can help us to communicate with others?

                                                                                                       

5. What do they help us to do?

                                                                                                       

判断题