which:
1.Football is a game which is liked by most boys.
2.This is the pen (which) he bought yesterday.
3.My house,which I bought last year,has got a lovely garden.
4.Liquid water changes to vapor,which is called evaporation.
5.The sun heats the earth,which is very important to us.
who/whom:
6.The boys who are playing football are from Class One.
7.Yesterday I helped an old man who lost his way.
8.Mr.Liu is the person who/whom you talked about on the bus.
9.Mr.Ling is just the boy who/whom I want to see.
10.The man who/whom you met just now is my friend.
11.He is the man whom/who I talk to.
12.There is somebody here who wants to speak to you.
whose:
13.He has a friend whose father is a doctor.
14.I once lived in a house whose roof has fallen in.
15.The classroom whose door is broken will soon be repaired.
16.Do you like the book whose color is blue?
that:
17.The number of the people that come to visit the city each year rises one million.
18.Where is the man that I saw this morning?
19.Is this the book that you borrowed in the library?
20.Finally,the their handed everything that he had stolen to the police.