标题: 大全249 [打印本页] 作者: ninaluan 时间: 2004-1-28 11:34 标题: 大全249 249 Doctors still know little about how the Listeria bacterium is spread and why the disease it causes, listeriosis, afflicts some people in a contaminated area though it spares many others. (A) though it spares (B) where it spares (C) despite sparing (D) when sparing (E) while sparing 答案是E，我想请问一下when 和 while在这句话中的使用有什么区别吗？谢谢！作者: delldell 时间: 2004-1-28 12:06
while 有表示强烈对比反差