【单选题】When we were students we often stay up all night.
【单选题】两个碳原子之间共用( )形成的键称为单键
【判断题】电阻、电流和电压都是电路中的基本物理量。 ( )
【单选题】It was not until all the milu deer ________ that we realized we should build a natural park to protect them.
【单选题】下列表述不正确的一项是
D.
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