井下人员可以在无风、微风或瓦斯超限、有害气体浓度超限的区域内作业吗?
参考答案:
严禁。
It is not polite to _____ those persons in trouble. [ ]
A. laugh to
B. laugh with
C. laugh of
D. laugh at
所有避雷针应与避雷带相互()。