关系代词which
例句：This is a good book which I enjoy reading.
这句话定语从句中reading应该是宾语吧,那么which在从句里充当什么成分呢?不是说which必须充当主语或宾语,否则之前要有介词才行吗?如：
He is a man whom I enjoy working with.这里的working是宾语吧?
我也不想这么抠语法的，但是考试就爱考这些啊。