1。which能放在非限制性定语从句,而that不行。
2。that(指物,人)=which(指物)+who(指人)
3.在there be 句型中,只用that,不用which
4.在不定代词,如:anything, nothing, the one, all, much, few, any, little等作先行词时,只用that,不用which
5.先行词有the only, the very,the same,the last,just修饰时,只用that
6.先行词为序数词、数词、形容词最高级时,只用that
7.先行词既有人,又有物时