学习资料
[意 思]det. 哪个, 哪些
[例]  Which languages did you study at school? 你上学时学的都是哪些语言?
pron. 哪一个, 哪些
[例]  Which is my seat? 哪个座位是我的?
pron. (在句中作关系代词, 连接从句)
[例]  He invited us to dinner, which was very kind of him.
他邀请我们吃晚饭,他这么做真是太客气了。