Unit 7

2. catching too many fish in an area of the sea
4. noise, such as that from traffic, that upsets people where they live or work and is considered to be unhealthy for them
6. the waste produced by industrial activity
10. waste material or unwanted things that you throw away
11. a gradual increase in world temperatures caused by gases
13. an accident in which oil has come out of a ship and caused pollution
16. a layer of air containing ozone high above the earth that prevents harmful ultraviolet light from the sun from reaching the earth
18. the contamination of water bodies, with a negative impact on their uses
19. a fire burning in an area of land with many trees
20. the cutting down of trees in a large area,

1. a fire burning in an area of land with many trees
3. an eruption of molten rock, hot rock fragments, and hot gases through a volcano,
5. a situation in which there is not enough food for a great number of people
7. rain that contains large amounts of harmful chemicals
8. electromagnetic radiation of wavelengths of 10–400 nanometers
9. the deposition of solid or liquid waste materials on land or underground in a manner that can contaminate the soil
12. a violent wind that has a circular movement,
14. harmful substances in the air,
15. a sudden violent movement of the earth's surface,
17. to cause to fill or become covered with water,