于是他拿出火绒箱,并敲击打火石.Then he took out his tinderbox and struck the flint.只要它的质地接近打火石, 卡森就有足够的信心将它磨成一把耐用的小刀.If it chipped like flint, he could make a serviceable knife out of it.他觉得他扯了那么一通打火石的事, 现在有点害怕.But thinking he had said...
科学家根据那些化石的骨骼结构确定其年代.Scientists have dated the fossils by their bone structure.有两个因素对生物化石的保存是有利的.Tow factors are favorable for the preservation of organisms as fossils.它们是怎样变成化石的?How did they become fossils?...
We can gain the isochronous - modulus curves from the curves of stress - strain ratios.根据岩石蠕变的应力 - 应变比曲线可以近一步分析得到等时模量曲线.Isochronous stratigraphic interfaces are one of the most important marks of developing process of a ...