|指人||who / that||who / whom / that / x||whose||when/ where / why|
|指物||which / that||which / that / x||whose|
如：He is the man who / whom / that / x I saw yesterday. （宾语）
A prosperity which / that had never been seen before appears in the countryside.
Please pass me the book whose cover is green. （定语）
This is the college where / in which I stayed two years ago. （地点状语）
Their child is at the stage _____ she can say individual words but not full sentences.
A. why B. where C. which D. what