1. 人教修订版 高中二年级 ( 下 ) Unit 13

3. Reading

4. Talk about the earth and the importance of water for life. Animals and plants cannot live without water. 1.What is our earth made up of ? 2.What do you think of the role water plays in our daily life ? 3.Could you please give some examples ? Our earth is mostly made up of waters. tortoise

5.  water.wmv water.wmv

6. What is water made up of ? The molecule of water is made up of two hydrogen atoms and one oxygen atom.

7. What properties or characteristics do you know about water? colorless tasteless having no fixed shape three forms feeling wet keeping level ? absorbing heat propertiesproperties

8. The paper won’t fall off. Because the air pressure can hold the paper and the water won’t flow out.

9. The water and the oil won’t mix. The oil floats on the water. It is because the densities of them are different. Water has larger density and mass.

10. The chalk will dissolve in the water. It is because water has the ability to dissolve the soluble ( 可溶解的 ) things and matters.

11. The ice cube floats on both salt water and fresh water, but ice dissolves faster in salt water. Because ice has smaller density and it can float on the fresh water and salt can help dissolve.

12. While-reading The properties of water Ocean Motion Heat Capacity Salinity Chemical Structure Density

13. True or False 1. Water is a liquid at room temperature, and it has a relatively high freezing point. 2. The reason why water can dissolve most substances on earth is that water has high heat capacity. T F

14. 3. Like all the other substances, water gets smaller when it freezes. 4. Pure water has a higher freezing point and lighter than salt water. 5. The salinity of the earth’s oceans is about 3.5%. 6. When water freezes, its density increases. F F F T

15. 7. Other recourses such as oil, gas, gold etc is as precious as a drop of rain. 8. There are about five billion species in the oceans ranging from the tiniest plankton to giants like sharks and whales. T F

16. 9. The water molecule is made of two hydrogen atoms and one oxygen atom. 10. Pure water has a higher freezing point and is lighter than salt water. 11. If a substance has a density 888kg/ m3, it will float on Water. F T T

17. 12. The heat capacity is relatively high, so that most animals don’t like living in it. 13. The most important thing we can learn about water, is that we must protect it and use it wisely. F T

18. ( )1.Based on Para. I, the author tells us that there are various species in the oceans, indicating that ____. A. Water plays a great role for marine life. B. Ocean is a good place for life. C. There are many reasons for tiniest plankton and giants like sharks and whales D. Ocean is part of the earth ( )2.The water in the ocean is always moving in that _____. A. The temperature of sea water is relatively high. B. Water’s density affect changes in salinity and temperature. C. Changes in salinity and temperature have effect on water’s density. D. Waters in rivers always flow into the ocean. ( )3.Generally speaking,human beings are ______ to large or suddenly changes in temperature. A. generous B. objective C. subjective D. sensitive Reading Comprehension A C D

19. Properties of Water Para.1 chemical structure Para.2 salinity Para.3 Density Para.4 Heat Capacity Para.5 Ocean motion Para.6 How the text is organized.

20. chemical structure of water Para.2 water molecule two hydrogen atoms one oxygen atom The water molecule is made up of two hydrogen atoms and one oxygen atom. The chemical structure of water makes it an excellent medium for life and also makes it different from almost everything else on earth. Key points:

21. salinity Para.3 sea water dissolved solid and gases pure water Key points: The salinity of the earth’s oceans is about thirty-five parts per thousand. There are about 35 grammes of dissolved solids and gases in one kilogramme of water. Sea water consists of dissolved solid and gases as well as pure water. = salt water Compared with pure water, Salt water has a low freezing point and is heavy.

22. Density Para.4 massvolumeDensity key points : Density is the relationship between mass and volume, measured in kilogrammes per cubic metre. The density of pure water is 1,000 kg/m3. One cubic metre of water weighs one thousand kilogrammes.

23. Heat Capacity Para.5 the amount of energy it takes to raise the temperature of a substance by one degree centigrade waterheat absorb and give off The ocean has a stable environment in that water can absorb and give off heat to keep both the temperatures of the ocean and the earth steady. relatively high Heat Capacity

24. Ocean motion Para.6 water in the ocean always moving changes in salinity and temperature water’s density affect It is very important to learn about the properties of water. We must protect water and use it wisely. Water is what makes life possible.

31. Language points 1. range from…to…: vary in a specified limits e.g. The temperatures here range from 10 to 30°C. 这儿的气温变化在 10 度至 30 度 之间

32. 2. all the way e.g. Mrs Wang came all the way here. 王夫人径直到这儿来了。 3. …makes it an excellent medium… make + n.+ n. e.g. I want to make my sister a pianist. 我想使我的妹妹成为一个钢琴家。

33. 4. …make it different from… make it + adj. … e.g. You must make it clear that why you are late for school. 你必须讲清楚你迟到的原因

34. 5. …is made up of … e.g. The water molecule is made up of two hydrogen atoms and one oxygen atom. 6. break down: 分解, 分化 e.g. Chemicals in the body break our food down into useful substances. 人体中的化学元素把食物分解成有用 的物质。

35. 7. mix ….with: 把 … 和 … 混起来 mix joy with sorrow 悲喜交集 8. affect: 影响 ; 使感染 e.g. Smoking affects health. 9. freezing: adj. 极冷的 frozen: adj. 已经结冰的 a freezing glance 冷淡的一瞥 be freezing cold 冰冻一样地冷

36. 10. mass: quality ( 质量 ) the masses 群众, 民众 e.g. The masses have boundless creative power. a mass of… 大量的 …… e.g. Before the rain, the sky was a mass of clouds.

37. 11. …is measured in… measure v. e.g. Whether a girl is beautiful or not is measured by her soul. measure n. e.g. Kilogramme is the measure of weight.

38. 12. absorb: take in e.g.. The ice absorbs heat and turns into water. absorb one’s attention=draw one’s attention 13. stable: balanced a stable relationship 稳定的关系 a stable man 一个稳重的人

39. 14. sensitive: 对 ….. 敏感 be sensitive to e.g. You should be sensitive to the change of the society. 15. steady: 平稳的 ; 稳固的 ; 稳定的 be steady in one’s purpose 意志坚定的

40. e.g. If you are steady in your purpose, your dream will come true. make steady progress 取得持续进步 a steady man 一个稳重的人 16. add…to: 把 … 加到 … 上 / 里 add fuel to the flame 火上加油 add up to 总共

41. Homework 1. Finish exercises in the Practicing in the Workbook. 2. Preview the Integrating Skills.