掘进工作面施工钻孔的电气设备的电源必须和作业场所的局部通风和甲烷传感器实现风电和（）闭锁。
参考答案：瓦斯电
Teenagers ______ social experience, so they are easily ______ when they first step into society.
A．lack; taken up
B．lacking in; taken over
C．a lack of; taken on
D．lack; taken in
熔焊冶金特点是什么？
