Combine these sentences using the appropriate relative pronouns

III. Combine these sentences using the appropriate relative pronouns.  

1)     This is the man. The man gave Peter a dictionary.

2)     The ring was very expensive. He presented it to her on her birthday

3)     This is an interesting book. It is on wild animals.

4)     The boy is my friend. He is standing over there.

5)     Mary still remembers the year. She graduated in that year.

6)     Do you know the man? The police arrested him yesterday.