V.
1. Because of his laziness, he fails.
2. Because of her richness, she buys many things
3. Because of Ba not coming, he still knows in advance.
4. Because the bad food, I didn't eat.
5. Because of his new bike, he goes very quickly.
6. Because she was ill, she stayed at home.
7. Because he was poor, he didn't buy anything.
8. Because she is late, she is sad.
9. Because her result was bad, she felt sick.
10. Because the pen is good, he writes well.
11. Because of a big wind, he stayed at home.
12. Because of a bad cold, he stays at home.
IV>
1. if you don't practice more, you will forget.
2. If we aren't careful, we'll have accidents.
3. If you come back today, you will meet her.
4. If you aren't quiet, you will be punished
5. If Lan weren't late, her teacher wouldn't be angry.
6. If Lan didn't walk fast, she wouldn't catch the bus.
7. If they were coming, we would be happy.
8. If she didn't get wet, she wouldn't feel ill.
9. If he drives carefully, he will be safe.
10. If Nam didn't spoke quickly, I would understand him
11. If she weren't new, she would know some friends.
12. If they were here, I would meet them.