2.
1: Nam got wet because he forgot his umbrella
2: It's raining so we cannot go to the beach
3: He was tired but he tried to complete his homework
4: The camera didn't work so Mr. Robinson took it back to the shop
5: I'd love to play volleyball but I have to complete my homework
6: Mai wants to go home because she feels sick
7: Nga is hungry since she hasn't eaten all day
8: If the rice paddies are polluted, the rice will die
9: The oil will pollute the sea that people are worried
10: The weather was bad so we didn't enjoy our holiday
11: I often go to school with the boy who my neighbor's son
12: The man who spoke to you is my father
13: I lost a pen which is very good
15: Although he is very tired, he has to finish his homework
3.
1: to listen
2: using
3: will have
4: reduce