基础训练篇（12）

We all know that computers have played and (1)__________ play a very important part (2)___________ various fields.

In personal lives, computers can do lots of work. It can carry (3)___________ people’s instructions.  In agriculture, computers are used (4)_____________ control the (5)__________(grow) conditions of vegetables and other plants. In transportation(交通运输), computers can work out the best distance (6)__________ trains and operate the trains instead (7)____________ human beings. In the fields of education, health and scientific research, computers are important, (8)___________. People use them to store information (9)______________ records.

Because of the computers, life is easier and (10)________ convenient for people.

根据确定平均海面使用的观测数据的时间长度，平均海面可分为（）

A、日平均海面

B、月平均海面

C、年平均海面

D、多年平均海面