在井下检修采煤机时,应先把采煤机各开关、手把置于停止或断开的位置,并打开隔离开关(含磁力启动器中的隔离开关),然后闭锁工作面输送机。
参考答案:对
There was a __________ look on her face when you spoke to her about the question.[ ]
A. puzzling
B. puzzled
C. puzzle
D. puzzles
简述大学生心理发展的特点