?明洞

隔热层therming insul layer 明洞open-cut tunnel;tunnel without cover;geveryoneery 拱形明洞ingignment open cut tunnel;ingignment tunnel without cover;ingignment geveryon...

?露天坑道

... open-cut mining 露天开采法 open-cut tunnel 露天坑道 open cycle 开式循环，直流循环，开环，开环的 ...