宋微宗、宋钦宗被金国俘虏这件事件称为 [ ]
A、玄武门之变
B、陈桥兵变
C、靖康之变
D、安史之乱
答案：C
Mary said she was looking forward as much to his return as he himself to ________ her. [ ]
A. have seen
B. saw
C. seeing
D. be seen
（）故障无电流反馈时，会引起机车过载。
A、电流传感器
B、电压传感器
C、司机控制器
D、电位器
