变压器内部故障时，（）继电器上接点接（）回路，下接点接开关（）回路。
参考答案：瓦斯；信号；跳闸
---Hi, Tom. Do you have any idea where Jane is?
---She _________ in the classroom. I saw her there writing her composition just now.
A．shall be
B．could be
C．must be
D．might be
产后腹痛血虚证的治法是（）
A．养血活血
B．补血益气
C．行气养血
D．活血止痛
E．活血化瘀，散寒止痛
