关系代词 = 连词 + 代词;
That is the man. The man gave me the book.
That is the man 【and】【he】 gave me the book.
That is the man 【who】 gave me the book.
那位就是给我这本书的人。
who gave me the book 修饰the man,是定语;

That is the teacher 【who / that】 teaches us English.
那位就是教我们英文的老师。
The dog 【whic / that】 is lying on the floor is lucky.
躺在地板上的那只狗是lucky.
I like the boy.
The boy is playing basketball.
I like the boy who is playing basketball.
I like the boy that is playing basketball.
我喜欢那个正在打篮球的男生。
The towel is hers.
The towel is on the table.
The Towel which is on the table is hers.
The towel that is on the table is hers.
在桌子上的那条毛巾是她的。
The man lives upstairs.
The man always goes out at midnight.
The man who always goes out at midnight lives upstairs.
The man that always goes out at midnight lives upstairs.
住在楼上的那个那人老是在半夜外出。
A student is a person who studies at school.
Students are persons who study at school.
学生就是在学校学习的人。
He is the only one of the students that has finished his studies without any support from his family.
他是唯一 一个 没有家人 支持而完成学业的学生。
I know who can swim fast. // 疑问代词
我知道谁游的最快。
I know a boy who can swim fast. // 关系代词
我认识一个游泳很快的男孩。

He has a friend whose mother is singer.
他有一个妈妈是歌手的朋友。
I’m looking for a book whose subject is basketball.
我正在找一本主题是篮球的书。
The boy is Curry.
The girl’s eyes are big.
The boy whose eyes are big is Curry.
那个眼睛很大的男孩是Curry。
The dog is called Lucky.
The dog’s tail is short.
The dog whose tail is short is called lucy.
那只短尾巴的狗叫Lucy。

She is the girl who I met (缺宾) at the party.
She is the girl whom I met at the party.
She is the girl that I met at the party.
She is the girl I met at the party.
她是我在派对上遇见的女孩。
I’m reading a book which I borrowed from the library.
I’m reading a book that I borrowed from the library.
I’m reading a book I borrowed from the library.
我正在阅读从图书馆借来的书。
The man is my teacher.
I called him last night.
The man whom I called last night is my teacher.
The man I called last night is my teacher.
我昨天打电话给他的那位男士是我的老师。
This is the house.
We’ll hold a party in the house.
This is the house which we’ll hold a party in.
这是我们将要举办派对的房子。
October is the moth.
I was born in the month.
October is the moth which I was born in.
十月是我出生的月份。
I heard the news that Curry told (缺宾语)to you.
我听说了 Curry告诉你的消息了。
双宾动词(授予动词) tell
tell sb sth
tell sth to sb;
关代后+不完整句(缺主,或缺宾)
I heard the news that Curry passed the entrance exam.
我听说了Curry 通过入学考试的消息。