That/which 用 which 引导的从句一定要用逗号“,” 分开。 用 that
引导的从句不要分开。 经常出现的错误是该用 that 的地方用了 which。 That/which
经常用来引导修饰从句. 如果修饰从句可以省略掉而不影响句 子的完整性，也就是非限制性从句, 用 which, 并用逗号把修饰从句从主句分 开. The
recovered dogs, which were
treated with antibiotics, are released. 如果修饰从句不可以省略掉, 也就是限制性从句, 那就用 that，并不用逗号 分开. Dogs
that were treated with
antibiotics recovered.