焊接点区域加温时，一般元器件的焊接时间为3秒，场效应管、MOS等

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问题单项选择题

焊接点区域加温时，一般元器件的焊接时间为3秒，场效应管、MOS等电路等控制在（），接线柱、插头、插座、钮子开关、波段开关、焊片等可控制在3–5秒。

A、1秒内

B、2秒内

C、3秒内

D、4秒内

答案

参考答案：B

句型转换

将下列简单句合并为由that引导的定语从句的复合句。

1. Is there a hospital near here? Jack works in the hospital.

_________________________________________.

2. Do you like the pen? I bought it last week.

_________________________________________.

3. My father took many photos in Australia. They were liked by his friends.

_________________________________________.

4. This is a nice picture. Tom drew the picture last year.

_________________________________________.

5. The woman is my aunt. She wears a pair of white shoes.

_________________________________________.

判断题

经常保养是指由轨枕以下至钢轨顶面进行多项配合修理。