1. 高二年级 英语 授课者：蒋立耘

2. Water is a must to life. Without water, life would not exist.

3. 22 nd, March

4. World Water Day 2005 was "Water for Life". The theme for World Water Day 2004 was “Water and Disaster”. The theme for World Water Day 2006 was “Water and Culture”.

5. The theme for World Water Day 2007 was “Coping with water scarcity”. The theme for World Water Day 2008 will be “Sanitation”.

6. Conserve Water A world without water is dead. SAVE WATER to remain alive and healthy.

7. Do not let your tear be the last drop of water in the world !

8. properties What properties or characteristics do you know about water? colorless tasteless odorless three forms feeling wet absorbing heat dissolving

9. 1.What’s the sea water ? A. It’s a mixture of dissolved gases and solids with fresh water. B. Sea water is lighter than pure water. 2. Does the sea freeze ? A. Yes. B. No. Water Quiz!

10. 3.Water contracts(gets smaller) when it freezes. A. Yes. B. No. 4. Rainwater is the purest form of water. A. Yes. B. No. Water Quiz!

11. 5.It takes more energy to heat cold water to 212 ºF than it does to change 212 ºF water to water steam. A. Yes. B. No. 6. What’s heavier, sea water or pure water ? A. Sea water. B. Pure water. Water Quiz!

12. 7. Put an ice cube in a glass of pure water, what happens ? A. It floats in the water. B. It sinks. 8. Put an ice cube in a glass of salt water, what happens ? A. It floats on the water. B. It sinks. Water Quiz!

13. 9. What state is water in at room temperature? A. Liquid. B. Solid. C. Gas. 10. The chemical structure of water is_____ A. Two hydrogen atoms and one oxygen atom. B. Two oxygen atoms and one hydrogen atom. Water Quiz!

14. Exx.1.2. P.95

17. What do these numbers mean? 40 20 There is enough air to last about 40 minutes in a metal bottle. They dive a depth of 20 meters.

18. 1.First, divers carry on their backs a _____ ______which is filled with ___. 2.Next, divers carry heavy _____ _______in a ____ around their body. 3.For one thing, you might have ________ with your ____ ______. Fill in the missing words(1): metal bottleair weightsbelt problems air bottle metal

19. 4.There are also dangerous ______ of ____ that you must _____ _____ ____. 5.If you don’t have the necessary ________, it can be both ________ and ___________. Fill in the missing words(1): types fish look out trainingdifficult dangerous for

20. AdviceReasons Know your limits. Don’t hold your breath. Diving deeper or longer than you used to can be dangerous. Result in serious lung injuries. Don’t dive within 12 hours of a flight. Cause dangerous gases to enter the blood. Fill in the chart (2):

21. Listen to part 2 of the tape: 1.It is important to understand that ________ is very important. 2.If you don’t have enough ____________, you mustn’t dive _______ or ________ than what you are used to. safety experience deeper longer Fill in the missing words(2):

22. 3.If a diver holds his breath,__________ difference between the air in the______ and the________ may become so great. 4.Singing a song while diving is the simple way to ________ ________that you are breathing _________. lungs outside pressure make sure normally Fill in the missing words(2):

23. Vocabulary Exx.1~ 2 (P.96~97) Word study Exx.1 (P.21)