宾语从句：有where引导句子在整个句子充当宾语成分,就是宾语从句.eg:一定在动词后面；i don't know where he came from.状语从句：where等引导词在整个句子中充当状语成分的就是状语从句.eg:句子位置不限；where there is a will，there is a way.where从句也可以放到主句后面。