Read the definitions carefully and select the correct words.
1. the mixture of gases that surrounds the Earth
2. the most northern point on the surface of the Earth
3. the most southern point on the surface of the Earth
4. to do something that produces an effect or change in something or in someone’s situation
5. a permanent change in weather conditions
6. to become impossible to see any longer
7. an illness which affects a person, animal, or plant
8. a change that is caused by an event, action etc
9. concerning or affecting the air, land, or water on Earth
10. to go down to a lower level, amount, price etc
11. a situation in which a large number of people have little or no food for a long time and many people die
12. a substance such as air, which is not solid or liquid, and usually cannot be seen
13. affecting or including the whole world
14. a general increase in world temperatures caused by increased amounts of carbon dioxide around the Earth
15. happening slowly over a long period of time
16. slowly, over a long period of time
17. the seeds of crops such as corn, wheat, or rice that are gathered for use as food, or these crops themselves
18. to have a bad effect on something
19. causing harm
20. a period of time such as a few weeks when the weather is much hotter than usual
21. belonging to or relating to people, especially as opposed to machines or animals
22. a subject or problem which people are thinking and talking about
23. a substance that is not a solid or a gas, for example water or milk
24. if something solid melts or if heat melts it, it becomes liquid
25. to make air, water, soil etc dangerously dirty and not suitable for people to use
26. the process of making air, water, soil etc dangerously dirty and not suitable for people to use, or the state of being dangerously dirty
27. to say that something will happen, before it happens
28. if something or someone is predictable, you know what will happen or what they will do
29. a tropical forest with tall trees that are very close together, growing in an area where it rains a lot
30. to increase in number, amount, or value
31. a firm object or substance that has a fixed shape, not a gas or liquid
32. if something spreads or is spread, it becomes larger or moves so that it affects more people or a larger area
33. the air, water and land in or on which people, animals and plants live
34. changing a lot so it is impossible to know what will happen