underground mining
短語詞組
- underground col mining 地下采煤
- underground coal mining 地下采煤
- underground E mining 地下開采
- Underground melting mining 地下熱熔開采
- underground d mining 地下采礦
- underground coal mining method 地下采煤方法
- underground bench mining 井下梯段采礦法
- underground trackless mining vehicle 地下無軌采礦車輛 返回 underground mining