大綱版高二英語 Unit 13 The properties of water reading教學(xué)課件

1、Reading 廈門二中廈門二中 鄭芃芃鄭芃芃The properties of waterWarming up How is the water being used?Where does water come from ?What is water made up of ? The molecule of water is made up of two hydrogen atoms and one oxygen atom.Pre-reading1.What are the properties of water? While-readingWhile-readingThe properti

2、es of waterOcean MotionHeat CapacitySalinityChemical StructureDensity1. What is the salinity of the earths oceans? The salinity of the earths oceans is about thirty-five parts per thousand, meanig that there are about 35 grammes of dissolved solids and gases in one kilogramme of water.2.Why is the w

3、ater in the ocean always moving?=How many parts are there in the passage?=Part 1(para1): the properties of water;Part2(Para2): chemical structure of water-H2OPart3(Para3): salinity- the percentage of salt.Part4(Para4): DensityPart5(Para5): heat capacityPart6(Para6-7) Ocean motionActivity 3. Finding

4、Topic Sentences of the text:PropertyWhat is it?Chemical structureThe water molecule is made up of two hydrogen atoms and one oxygen atom. The water molecule is polar it has a slightly negative and a slightly positive end.Post-readingPropertyWhat is it good for?Chemical structureBecause water is pola

5、r, it break down nutrients quickly. The chemical structure of water also makes it different from most other substances: it is a liquid at room temperature and has a relatively high freezing point.PropertyWhat is it?DensityDensity is the relationship between mass and volume.PropertyWhat is it good fo

6、r?DensityThe density of water helps small creatures float. Because the density of water decreases when it freezes, the oceans never freeze totally.PropertyWhat is it?Heat capacityHeat capacity is the amount of energy it takes to raise the temperature of a substance one degree centigrade.PropertyWhat

7、 is it good for?Heat capacityThe heat capacity of water keeps the oceans at a steady temperature, which makes it a good place to live for creatures that are sensitive to sudden changes in temperature. The water in the oceans also keeps the temperature of the earth steady.Language points1. range from

8、to: vary in a specified limitse.g. The temperatures here range from 10 to 30C. 這兒的氣溫變化在這兒的氣溫變化在10度至度至30度度之間之間2. all the way e.g. Mrs Wang came all the way here. 王夫人徑直到這兒來了。王夫人徑直到這兒來了。3. makes it an excellent medium make + n.+ n. e.g. I want to make my sister a pianist. 我想使我的妹妹成為一個(gè)鋼琴家。我想使我的妹妹成為一個(gè)鋼琴家。

9、4. make it different from make it + adj. e.g. You must make it clear that why you are late for school. 你必須講清楚你遲到的原因你必須講清楚你遲到的原因 5. is made up of e.g. The water molecule is made up of two hydrogen atoms and one oxygen atom. 6. break down: 分解分解,分化分化e.g. Chemicals in the body break our food down into u

10、seful substances. 人體中的化學(xué)元素把食物分解成有用人體中的化學(xué)元素把食物分解成有用的物質(zhì)。的物質(zhì)。7. mix .with: 把把和和混起來混起來 mix joy with sorrow 悲喜交集悲喜交集8. affect: 影響影響; 使感染使感染 e.g. Smoking affects health.9. freezing: adj. 極冷的極冷的 frozen: adj. 已經(jīng)結(jié)冰的已經(jīng)結(jié)冰的 a freezing glance 冷淡的一瞥冷淡的一瞥 be freezing cold 冰凍一樣地冷冰凍一樣地冷10. mass: quality (質(zhì)量質(zhì)量) the m

11、asses 群眾群眾, 民眾民眾 e.g. The masses have boundless creative power. a mass of 大量的大量的e.g. Before the rain, the sky was a mass of clouds.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.12. absorb: take in e.g

12、. The ice absorbs heat and turns into water. absorb ones attention=draw ones attention13. stable: balanced a stable relationship 穩(wěn)定的關(guān)系穩(wěn)定的關(guān)系 a stable man 一個(gè)穩(wěn)重的人一個(gè)穩(wěn)重的人 14. sensitive: 對(duì)對(duì).敏感敏感 be sensitive to e.g. You should be sensitive to the change of the society.15. steady: 平穩(wěn)的平穩(wěn)的; 穩(wěn)固的穩(wěn)固的; 穩(wěn)定的穩(wěn)定的 be

13、 steady in ones purpose 意志堅(jiān)定的意志堅(jiān)定的e.g. If you are steady in your purpose, your dream will come true. make steady progress 取得持續(xù)進(jìn)步取得持續(xù)進(jìn)步 a steady man 一個(gè)穩(wěn)重的人一個(gè)穩(wěn)重的人16. addto: 把把加到加到上上/里里 add fuel to the flame 火上加油火上加油 add up to 總共總共Homework1. 1.Surf the internet and get more information about water and ocean using search engines like