which 与that 的区别： 1.先行词是everything, nothing, anything, something, much, little, none等不定代词，引导定语从句用that。 2.先行词被形容词最高级或序数词修饰时，引导定语从句用that。 3.先行词被any, some, no, much, few, little, every, all, very, only, last 修饰时,引导定语从句用that。 4.先行词中既有人又有事物时，引导定语从句用that。 5.在介词后面，要用which,不用that 。 6.非限制性定语从句用which引导，不用that。