1. After David had gone home, we arrived.
2. When we got out of the office, the light had gone out.
4. Before my mother came home, my father had watered all the plants in the garden.
5. Because there was a loud noise next to my door last night, I couldn't sleep.
6. The roads are flooded due to the heavy rain.
7. Eating too much sugar can lead to health problems.
9. If the factory weren't located near our village, there wouldn't be air pollution and noise pollution.
10. If the local people had fresh water, they wouldn't have to use water from the polluted river.
11. If people didn't throw rubbish in the street, it would look attractive.
12. Objects can be moved as big as a car by tornadoes.
13. Chess has been played for around two thousands years.
14. Residents of flooded villages were taken to to a safe place last night.