who，that在很多情況下可以通用，但是有些情況只能用who:
1. 先行詞是one, ones, anyone的時候宜用who.
One who has nothing to fear for oneself dares to tell the truth.
The ones who flatter me don’t please me.
Don’t tell anyone about the news who oughtn’t to know it.
Anyone who fails to finish the task given should be criticized.
2. 先行詞為those的時候，宜用who為關係代詞
Those who were not fit for their work could not see the beautiful clothes
made of the magic cloth.
Those who want to go to the Great Wall sign up here.
3. 當先行詞有比較長的後置定語的時候
I met a foreigner in the street yesterday who could asked me questions in
Chinese.
4. 一個句子中帶有兩個定語從句，其中一個定語從句的關係代詞為that,另一個則用
who.
The boy that you met last night is the group leader who studies very hard.
5. 在there be 開頭的句子中
There is an old man who wants to see you.
There are many young men who are against him.
一般沒有隻能用that不能用who的情況，能用that的句子，也能用who
who，that在很多情況下可以通用，但是有些情況只能用who:
1. 先行詞是one, ones, anyone的時候宜用who.
One who has nothing to fear for oneself dares to tell the truth.
The ones who flatter me don’t please me.
Don’t tell anyone about the news who oughtn’t to know it.
Anyone who fails to finish the task given should be criticized.
2. 先行詞為those的時候，宜用who為關係代詞
Those who were not fit for their work could not see the beautiful clothes
made of the magic cloth.
Those who want to go to the Great Wall sign up here.
3. 當先行詞有比較長的後置定語的時候
I met a foreigner in the street yesterday who could asked me questions in
Chinese.
4. 一個句子中帶有兩個定語從句，其中一個定語從句的關係代詞為that,另一個則用
who.
The boy that you met last night is the group leader who studies very hard.
5. 在there be 開頭的句子中
There is an old man who wants to see you.
There are many young men who are against him.
一般沒有隻能用that不能用who的情況，能用that的句子，也能用who