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问题 单项选择题

带平衡电抗器三相双反星形可控整流电路中，平衡电抗器的作用是使两组三相半波可控整流电路（）。

A、相串联

B、相并联

C、单独输出

D、以180°相位差相并联

答案

参考答案：D

完形填空
请认真阅读下面短文，并根据所读内容在文章后图表中的空格里填入最恰当的单词。注意：每空只能填1个单词。
Most people feel lonely sometimes, but it usually only lasts between a few minutes and a few hours. This kind of loneliness is not serious. In fact, it is quite normal. For some people, though, loneliness can last for years. Now researchers say there are three different types of loneliness.
The first kind of loneliness is temporary. This is the most common type. It usually disappears quickly and does not require any special attention. The second kind, situation—for example, family problem, the death of a loved one, or moving to a new place. Although this kind of loneliness can cause physical problems, such as headaches and sleeplessness, it usually does not last for more than a year.
The third kind of loneliness is the most severe. Unlike the second type, chronic（the opposite of “temporary”）usually lasts more than two years and has no specific cause. People who experience habitual loneliness have problems socializing and becoming close to others. Unfortunately, many chronically lonely people think there is little or nothing they can do to improve their condition.
Psychologists agree that one important factor in loneliness is a person’s social contacts, for example, friends, family members, co-workers, etc. We depend on various people for different reasons. For instance, our families give us emotional support, our parents and teachers give us guidance, and our friends share similar interests and activities. However, psychologists have found that, though lonely people may have many social contacts, they sometimes feel they should have more. They question their popularity.
Psychologists are trying to find ways to help habitually lonely people for two reasons: they are unhappy and unable to socialize and there is a connection between chronic loneliness and serious illness as heart disease, while temporary and situational loneliness can be a sad, and sometimes dangerous condition.
Loneliness and Disease
Three different types of小题1: 
The most common type is  小题2:  . It disappears quickly and  小题3: no special attention.
The second type is situation, which usually lasts for  小题4: than a year.
The   小题5:   kind is chronic, which means if people experience habitual loneliness, they’ll have problems socializing with others
An important
 小题6:  in
loneliness
With the help of Psychologists, we know a person’s social contact is one important factor.
We depend on a wide variety of people for different reasons. For instance, we have interests and activities  小题7:  to our friends’.
小题8:  people may have many social contacts, but they sometimes feel they should have more.
The    小题9:  
for finding ways to help the lonely people
One is that they are unhappy and unable to socialize.
The other is that temporary and situational loneliness can be a sad condition, sometimes   小题10:   too.
 
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判断题

使用U形管压力计测得的表压值与玻璃管端面面积大小有关。（）
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