各位大侠~~请教请教~~ 这是这题的正确句子:Emily Dickinson's letters to Susan Huntington Dickinson, which were written over a period beginning a few years before Susan's marriage to Emily's brother and ending shortly before Emily's death in 1886,outnumber her letters to anyone else. 当中的which为什么正确呀,不是说which指代逗号前面的一个词么~~ 正确的which用法又是什么呢?