Natural Disasters

8. a mass of rock and earth falling unexpectedly down a steep slope.
10. someone who is working in a country where there is a war, no food, etc., in order to help people.
12. a dangerous or unpleasant situation which you have gotten into and from which it is difficult or impossible to escape.
14. a sudden violent movement of the earth's surface, sometimes causing great damage.
15. a violent wind that has a circular movement, found in the West Pacific Ocean.
16. a large valley with very steep sides and usually a river flowing along the bottom.
17. a violent wind that has a circular movement, especially in the West Atlantic Ocean.

1. The movement of water associated with the rise and fall of the tides.
2. a mountain with a large, circular hole at the top through which lava (= hot liquid rock) gases, steam, and dust are or have been forced out.
3. a long period when there is little or no rain.
4. a person who does something, especially helping other people, willingly and without being forced or paid to do it.
5. a person who continues to live, despite almost dying.
6. to fall down suddenly because of pressure or having no strength or support.
7. to cause to fill or become covered with water, especially in a way that causes problems.
9. an occasion when a volcano explodes, and flames and rocks come out of it, or the act of doing this.
10. a large amount of ice, snow, and rock falling quickly down the side of a mountain.
11. a fire that is burning strongly and out of control on an area of grass or bushes in the countryside.
13. to say or do something as a reaction to something that has been done or has happened.