精选优质文档-倾情为你奉上“介词+关系代词”引导的定语从句“介词关系代词”既可以引导限制性定语从句，也可以引导非限制性定语从句。在此结构中，关系代词指人时用whom，不可用who或that；指物时用which，不能用that；关系代词是所有格时用whose。但如果介词后置，则不受这种限制，关系代词还可以省去，尤其在口语中。如：1) Do you know the girl to whom our teacher was talking? = Do you know the girl (that/who/whom) our teacher was talking to?2) The school (that/which) my brother once studied in is very famous.= The school in which my brother once studied is very famous. 要确定关系代词前用什么介词，可以根据：（1）定语从句中动词和什么介词搭配（2）先行词常和什么介词搭配。如：My
