Howe carefully cultivated Daniel C. Roper, the Assistant Postmaster General.豪谨慎地和邮政副部长丹尼尔·C.罗珀拉近关系。The postmaster shook his head sorrowfully.邮差难过地摇了摇头。The postmaster was a very polite old man.这位邮政局长是个非常有礼貌的老人....
How do acids react on metals?酸对金属会起什么样的化学反应?By this mechanism, new phosphatides containing the fatty acids of phosphatidyl choline may be prepared.根据这个原理, 可以制备含有磷脂胆碱脂肪酸的新磷脂.Acylglycerol ( glyceride ) An ester of glycerol...
周围的矿井里的确有沼气聚积。Methane gas does collect in the mines around here.尽管矿井的安全状况有了很大改善，矿工的家属仍然害怕最糟的情况会发生。Though mine safety has much improved, miners' families still fear the worst.矿井中用钢制通风机来保持空气流通。The pit is ventilated by...