速度染发
rock,gold岩，金双语对照例句:1.For every 10g of gold, about a tonne of rock needs to be crushed. 因为每采10克黄金，大约需要粉碎1吨矿石。 2.Methane-generating bacteria might be living off hydrogen produced by rock, as studieskilometers down in south african gold mines have shown. 产生甲烷的细菌可能依靠岩石释放的氢为生，就象在南非金矿中数公里以下进行的研究所显示的那样
