定语从句I will never forget the day when I first met you on the

定语从句
I will never forget the day when I first met you on the seashore.
*I will never forget the days which/that we spent together in Xueyao Middle School.
**This is the hospital where my mother works.
**This is the hospital which/that we visited the day before yesterday
为什么一个可以用when where 但是另一个要that which

1.who指人在从句中做主语
(1) The boys who are playing football are from Class One. 在踢足球的男孩们是一班的.
(2) Yesterday I helped an old man who lost his way. 昨天，我帮助了一个迷路的老人.
2. whom指人，在定语从句中充当宾语，常可省略。（注：who和whom已无太大区别，可以通用。）
(1) Mr. Liu is the person (whom) you talked with on the bus. 刘先生就是在公交车上和你聊天的那个人.
(2) Mr. Ling is just the boy whom I want to see. 凌先生恰巧就是我想见的那个男孩.
(3) The man who/whom you met just now is my friend. 你刚刚见到的那个人就是我的朋友.
注意：关系代词whom在口语和非正式语体中常用who代替，可省略。
如果在从句中做宾语,就用whom或who.比如: He is the man whom/who I talk to. 他就是那个和我聊天的男人.
如果是在从句中作主语就只能用who.比如: He is the man who has an English book. 他就是那个有英语书的男人.
3.which指物，在定语从句中做主语或者宾语，做宾语时可省略
(1) Football is a game which is liked by most boys. 足球是大多数男孩都喜欢的游戏.
(2) This is the pen (which) he bought yesterday. 这是他昨天刚买的钢笔.
4. that指人时，相当于who或者whom；指物时，相当于which。
在定语从句中做主语或者宾语，做宾语时可省略。
(5) The number of the people that/who come to visit the city each year rises one million.
(6) Where is the man that/whom I saw this morning?
5. whose通常指人，也可指物，在定语从句中做定语
(1) He has a friend whose father is a doctor.
(2) I once lived in a house whose roof has fallen in.whose指物时，常用以下结构来代替
(3) The classroom whose door is broken will soon be repaired.
(4) The classroom the door of which is broken will soon be repaired.
(5) Do you like the book whose color is yellow?
(6) Do you like the book the color of which is yellow?
求采纳为满意回答。
再问： 不要复制啊 看不懂