LC主触头虚接、励磁机L或主发电机F的励磁绕组断路时，会造成主发电机无电压、电流。
参考答案：对
23. --- He is fifteen years older than you.
--- _______ Love has nothing to do with age.
A．What for?
B．How about it?
C．So what?
D．How come?
药用酶
