1. Have you ever been to any English speaking countries ?

2. We had better not throw rubbish on streets.

3. How about giving a presentation about water and air pollution.

4. New York is the biggest city in the USA but not the capital.

5. While I was waiting at the bus stop, it started to rain heavily.

II.

1. The flood victims were helped to rebuild their houses by Volunteers.

2. Before we started our work, she had explained eveything clearly.

3. If I didn't have to look after my younger sister, I could go out now.

4. If we don't hurry up, we will miss the last bus.

5. Despite being tired, he tried to finish his homework.

III.

1. It is interesting to go camping with friends in the summer.

2. Kangaroo is the symbol of Australia.

3. If I were you, I would plant vegetables in the garden.

4. A lot of trees can be saved by recycling used paper.

5. Noise pollution in big cities can lead to hearing problems.