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问题 单项选择题

使用稳压二极管时应注意极性不能接错，否则会造成电源（）。

A、短路

B、断路

答案

参考答案：A

改错题
短文改错。
     此题要求改正所给短文中的错误，对标有题号的每一行作出判断：
     如有错误（每行只有一个错误），则按下列情况改正：
     此行多一词：把多余的词用斜线(\)划掉，在该行右边横线上写出该词，并也用斜线划掉。
     此行缺一词：在缺词处加一个漏字符号(^)，在该行右边横线上写出该加的词。
     此行错一词：在错的词下划一横线，在该行右边横线上写出改正后的词。
     注意：原行没有错的不要改。
Dear editor,
My name is called Zhang Hong. I am a middle school 
student. When I go to the school every day, I can see a lot of
sellers outside around our school walls, sell vegetables, fruits, 
fish, meat and so on. Some even make dishes in the opening air.
They often shout at the top of their voices in order draw the
passers-by's attention. We could hear the noises in the classroom
and cannot concentrate on our lessons. Beside,they also make 
the streets dirt, smelly and crowded. What a shame! 
How we want to get the situation improved or have our
lessons in a quiet place! That's how I write to you for help!
1. _____
2. _____
3. _____
4. _____
5. _____
6. _____
7. _____
8. _____
9. _____                                          
10. _____
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单项选择题

祛邪可用于

A．推动作用
B．温煦作用
C．防御作用
D．固摄作用
E．气化作用
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