问题 单项选择题

在TT系统中,当SPD装在剩余电流保护器负荷侧,选择220/380V三相系统中的电涌保护器时,其最大持续运行电压Uc不应小于( )。(注:U0为低压系统中相线对中性线的标称电压)

A.1.1U0
B.1.15U0
C.1.5U0
D.1.55U0

答案

参考答案:D

阅读理解

阅读理解。

     Your body, which has close relations with the food you eat, is the most important thing you

own, so it needs proper treatment and proper nourishment (营养).The old saying "An apple a

day keeps the doctor away "is not as silly as some people think. The body needs fruit and

vegetables because they contain vitamin C. Many people take extra vitamins in pill form,

believing that these will make them healthy.

     But a good diet is made up of nourishing food and this gives all the vitamins you need. The

body doesn't need or use extra vitamins, so why waste money on them?

     In the modern western world, many people are too busy to bother about eating properly.

They  throw anything into their stomachs, eating hurriedly and carelessly. The list of illnesses

caused or made worse by bad eating habits is frightening.

1. "Your body has close relations with the food you eat." It really means that ______.

A. all kinds of food you eat can be made into your body

B. your body is made up of the food you eat

C. what you eat has great effect on your health

D. the more you eat, the fitter you will feel

2. In the modern western countries ______.

A. people don't want to pay more attention to their eating

B. lots of people's illnesses are caused or made worse by bad eating habits

C. people throw everything into their stomachs without chewing

D. people are only too busy to cook meals for themselves

3. From the passage we can draw a conclusion that if we want to keep healthy, we should ______.

A. only eat an apple a day

B. eat properly

C. take as many vitamin pills as possible

D. throw something into our stomachs slowly and carefully

问答题 简答题