锑的百分含量由各蓄电池生产厂自己掌握.The percentage of antimony may be left to the battery manufacturer.我国盛产锑.Antimony abounds in out country.锑能增加铸件的硬度.Antimony adds to the rigidity of the casting....
Many phrases in the last two chapters echo earlier passages.最后两章中的很多说法是对前面段落的呼应。As we have seen in previous chapters, visualization methods are varied.我们在前几章已经了解到，可视化方法是多种多样的。The author devotes the first three chapters t...