［定語從句］介詞+關系詞
1)介詞后面的關系詞不能省略。
2)that前不能有介詞。
3)某些在從句中充當時間，地點或原因狀語的"介詞+關系詞"結構可以同關系副詞when 和where 互換。例如：
This is the house in which I lived two years ago. 這是我兩年前住過的房子。
This is the house where I lived two years ago.
Do you remember the day on which you joined our club? 還記得你加入我們俱樂部的那一天嗎?
Do you remember the day when you joined our club?
更多定語從句講解 ,語法學習 http://vqdolsx.cn/show-113-328135-1.html
