coalmine造句 31. Coalface of Daizhuang Coalmine, the authors believe that the roof in lower seam will form the"block-bulk-beam"structure easy to fall after the mining of top ultra-close seam. 32. The safety of a main well headframe would be reduced significantly, due to increased loading capacity and higher vibration frequency in a coalmine.英文造句nuclear power stationnarrow marketself-loadingdisraeliuntwistedsteel factoryto the end of timecentral african republicmargin of safetyhitching postsupernaturallymove back and forthcongoleseclubheadsandmancapacity for workclay pigeonmissishremain firmquantitative economicsnone the worseat work onamerican plancatechinbilateral tradeflightedthdduck"s egground in