矿山井下电缆不应设置在( )中。
A．立井井筒
B．运输大巷
C．总回风巷
D．工作面回风巷
参考答案：C
---They are quiet, aren’t they?
---yes. They are accustomed ____at meals.
A．to talking
B．to not talking
C．to not talk
D．to talk
经济基础
