站间区间在单线上，以（）柱的中心线为车站与区间的分界线。
A、通过信号机
B、站界标
C、进站信号机
D、出站信号机
参考答案：C
Don’t waste your words any more; she is as ______ as a mule (骡子) and no one can persuade her.
A．reliable
B．stubborn
C．determined
D．tired
