可置于定语从句之首,也可以置于一个名词之后.如；The house whose roof is broken lies on the hill.= The house of which the roof is broken lies on the hill.= The house the roof of which is broken lies on t...还有一个问题，介词的选取要遵循什么原则介词的选取要“瞻前顾后”，有时根据前面的搭配，有时根据后面的搭配。这不好抽象的说，你多练练定语从句的题目，慢慢就会知道了。