Saving the planet

3. A period of unusually hot weather
5. not wet or sticky; without water or moisture
8. connected with the relation of plants and living creatures to each other and to their environment
9. a mark left on a surface by a person’s foot or shoe or by an animal’s foot
12. to remove the plug of a piece of electrical equipment from the electricity supply
15. things that you throw away because you no longer want or need them
17. a long period of time when there is little or no rain
18. to continue to have something and not give it back or throw it away
19. the natural world in which people, animals and plants live
20. used with uncountable nouns to mean ‘a smaller amount of’

1. an illness affecting humans, animals or plants, often caused by infection
2. the process of treating things that have already been used so that they can be used again
4. to send out something such as light, heat, sound, gas, etc.
6. Any substance like air that is neither a solid nor a liquid
7. covered with or containing liquid, especially water
10. to add dirty or harmful substances to land, air, water, etc. so that it is no longer pleasant or safe to use
11. large amounts of water covering an area that is usually dry; the fact of this happening
13. the act of using something in a careless or unnecessary way, causing it to be lost or destroyed
14. the regular pattern of weather conditions of a particular place
16. at a fairly high temperature in a way that is pleasant, rather than being hot or cold