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1. Before the volcano erupted, people had left the area.
2. After Mai had lived in Ha Noi for 5 years, she moved to Da Nang last month.
3. He got home after everything had already happened.
4. If today were my day off, I could go with you to the movies.
5. Noise pollution causes hearing problem.
6. The accident happened due to his careless driving./The accident happened because of driving carelessly.
7. If I knew his address, I could visit him.
8. Water pollution leads to the death of fish.
9. If I had enough money, I could buy a new dictionary.
10. Nam's mother said that he had to finish all those exercises before going out with his friends that night.
11. Lan said that she would hand in her asignment to the teacher the following day.
12. Water pollution made the fish in the lake die.
13. Nam said that he was going to visit his grandpa the following day.
