The brevity of the letter concerned me.我担心这封信写得太短。The letter was short — a simple recitation of their problem.信写得很短——只是简单地说了一下他们的问题。Then I saw the dateline -- 1924. The letter had been written almost sixty years earlier....
这种泥土是一种蓝青色胶质土,主要由蒙脱土和一些伊利土组成.The mud was a blue - gray plastic clay composed predominantly of montmorillonite with some illite.通过在聚丙烯中添加纳米蒙脱土的改性方法,开发了高模量聚丙烯专用料.High - modulus polypropylene compound was developed by means...