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问题 不定项选择

如图所示的四个电路中，已知电源电压为U且恒定不变，当开关S闭合时，能用电压表测出灯L2两端电压的电路是 [ ]

A．

B．

C．

D．

答案

BD

填空题
用方框中单词的适当形式填空。
do, does, don't, doesn't ,be
1. —Does he have a baseball?
    —Yes, he           .
2.           they need school things?
3. She              have sports things.
4. I             know her name.
5. Let's  _____ good friends.
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名词解释

DDAVP
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