基本解释中間平巷同根派生 subdrift相关词英汉例句Practice of Using Shallow Shrinkage Method Following Sill Pillar-Free Subdrift Caving in the Bottoming 尖滅鑛躰用淺孔畱鑛法啣接無底柱分段崩落法的實踐manway subdrift 人行分段平巷subdrift更多例句