求助一道英语初三语法题Thisistheschool____Istudiedtwentyyearsago.为什么是where?我们老师说初中定语从句的引导词,代指人时用who,whom代指物时用which那么school学校应该是物啊,怎么不用which用where?

　　求助一道英语初三语法题

　　Thisistheschool____Istudiedtwentyyearsago.

　　为什么是where?

　　我们老师说初中定语从句的引导词,代指人时用who,whom

　　代指物时用which

　　那么school学校应该是物啊,怎么不用which用where?