电动机有异响处置方法：（）。
A.检查下降控制线路
B.更换轴承
C.更换碳刷
D.更换或修复电阻
参考答案：B, C, D
The suspect insisted that he________the young girl and that he________immediately. [ ]
A. shouldn't murder; would be set free
B. hadn't been murdered; should set free
C. hadn't murdered; be set free
D. shouldn't be murdered; would set free
抽油机基础安装上水平面水平度每米允许误差（）mm，全长允许误差5mm。
A、0.5
B、1
C、2
D、3
