现阶段我国劳动力流动频率加快，劳动关系短期化趋势明显。()

spwm的输出脉冲电压加到电机上，所得到的电流波形接近于正弦波。() 点击查看答案&解析

A provisional agreement is one（）

A.that could benefit both of us
B.that you have finalized the delivery dates
C.that is made with certain conditions
D.then he could get a large discount

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