Відповідь:

1. Acid rain falling on forests has killed a lot of trees in the last 20 years.
2. The council is encouraging us to recycle more household rubbish.
3. Factories and vehicles produce a lot of dangerous fumes.
4. Pollution of the atmosphere has increased over the last 50 years, making the environment very dirty.
5. The effect of gases in the earth's atmosphere is preventing the earth from losing heat; this is called the greenhouse effect.
6. When fumes are released into the atmosphere, they rise slowly.
7. The hole in the ozone layer is getting larger every year.
8. If global warming continues, there is a danger that the polar ice-cap will start to melt.
9. We take all our empty bottles to the bottle bank so that the glass can be used again.
10. Long periods of drought have brought about the desertification of whole areas of central Africa.
11. Tigers, whales, and panda bears are all endangered species.
12. People are worried that soon whales will become extinct.
13. We should use fewer fossil fuels such as oil and coal and look to other energy sources such as solar power and tidal energy.