my brother graduated from university in 2006,（in which） lwas still a middle school student
问题描述：
my brother graduated from university in 2006,（in which） lwas still a middle school student
为什么用 in which
答
因为从句要表达,我在那里上学,这个.那里.实际上指university.Which指代university.去掉in
从句就成了i was still a middle school student univerdity讲的什么，什么去掉in，in which 是固定的，我说假如去掉in，关系代词就是指代先行词，为了避免重复，它帮先行词在从句中占据位置，表明上是which，而意思上是先行词的意思，严格意义上，不能称in which为固定结够，之所以用in是因为i was still a middle student in university.若把从句改为，i also graduate from this university那就应该用from which