Environment

4. to put something under the ground
6. animals or plants that may soon not exist because there are very few now alive
7. to get rid of something that you do not want or need
9. an unnecessary or wrong use of money, substances, time, energy, abilities, etc.
11. damage caused to water, air, etc. by harmful substances or waste:

1. a mixture of smoke, gases, and chemicals, especially in cities, that makes the atmosphere difficult to breathe and harmful for health:
2. the planet third in order of distance from the sun, between Venus and Mars; the world on which we live:
3. a gradual increase in world temperatures caused by gases such as carbon dioxide that are collecting in the air around the earth and stopping heat escaping into space
4. destroy, damage, or injure by heat or fire.
5. to put used objects or materials through a special process so that they can be used again
8. use again or more than once.
10. a substance that can cause death or serious illness if you eat it, drink it etc