Step by Step2000 第二册UNIT 12 News (III)（在线收听）

Unit 12 News (III)

A. tapescript:

1. An avalanche is a large amout of ice, snow, earth, rock or other materials sliding down the side of a mountain or falling down a cliff.

2. A mudslide is a slow-mving mudflow that moves down a gradual slope.

3. An earthquake is the sudden release of strain energy in the earth’s crust resulting in waves of shaking that radiate outwards from the earthquake source.

4. A cyclone is a storm or ystem of winds that rotates around a center of low atmospheric pressure, advances at a speed of about 30 to 50 kilometers an hour, and often brings heavy rain.

5. Hurricanes are tropical cyclones with winds that exceed 64 knots or 74 miles per hour and circulate about their centers in the western atlantic ocean.

6. A tornado is a violent destructive whirling wind usually accompanied with severe thunder, lightening, and torrents of rain, and commonly of short duration and small breadth.

7. A typhoon is a type of violent tropical storm with strong circular winds that exceed 74 mph. It happens especially in the pacific ocean.

8. A drought is a period of dryness especially when prolonged that causes extensive damage to crops or prevents their successful growth.

9. A flood is a rising and overflowing of a body of water especially onto normally dry land.

10. A forest fire is a wild fire or an uncontrolled fire that is burning in frest, grass or other areas of vegetation.