Help "relative clause"

Hello everybody:


I need help to understand about How to use relative clause, Which, that and who.

Can you help me?? Thanks everybody.

http://www.usingenglish.com/glossary...ve-clause.html
http://www.usingenglish.com/glossary...ve-clause.html
http://www.usingenglish.com/glossary...ve-clause.html
http://www.usingenglish.com/glossary...e-pronoun.html