问题描述: 用be previous to造句 1个回答 分类:英语 2014-11-07 问题解答: 我来补答 e previous to之前Enough materials should be collected previous to writing.写作之前要收集足够的材料.The new pandemic H1N1 actually turns out to be related to previous pandemic strains.新的流行性的H1N1实际上已经变得和以前的流行的变种有关系. 展开全文阅读