在交流电压放大电路中，如果静态工作点选得过低，将引起（）失真。
A.截止
B.静点
C.饱和
D.放大
参考答案：A
离心泵运行时，滚动轴承的温度要求低于（）℃。
A、60
B、65
C、70
D、75
— Would you please repeat the grammar rules again?
— Of course, but I am sure that you _______ to me carefully, as I have told you twice already. [ ]
A. don't listen
B. wouldn't listen
C. weren't listening
D. aren't listening
