Our plan: 1.Get to know the properties of water. 2.Learn how to express a phenomenon in English. 3.Be aware of the significance of water.

Dear User, Shame to you all, the Ignorant( 无知的人 ), I am your life But you seem not to value me Give me all the respect For in me is eternal( 永恒的 ) life If you continue abusing( 乱用 ) me Surely, all forms of life will wither （枯萎，幻灭） away Have you ever imagined, Life without me? I tell you, it will be unbearable （无法忍受的） Think twice For every drop counts... A letter from ___________ water

Where there is water, there is life!

properties What properties or characteristics do you know about water? colorless tasteless liquid three forms feeling … transparent透明的

Structure of the passage Find out what properties the passage is going to explain to us. CHEMICAL STRUCTURE SALINITY THE PROPERTIES OF WATER DENSITY HEAT CAPACITY OCEAN MOTION skimming

Listen to the tape and find out the basic facts about life in the oceans Life on earth began in the oceans about ____ billion years ago; _____ of the living space on earth is in the oceans; There are about ______million (known) species in the oceans; What makes the ocean such a great place to live? The answer is ________ three 99% five water Para opening paragraphscanning

water molecule _______end ________end Chemical Structure Hydrogen Atoms Oxygen Atom 2 1 Para 2 dissolve If we add some salt into the pure water, what will happen to the salt? dissolvability 溶解性 positive negative

Salinity refers to dissolved gases and ________ mixed with _______ water. solids pure The salinity affects ________ & _________ weightfreezing point The salinity of the ocean is about _________ 35‰ Para 3 Salinity 1.As for the same volume of pure water and sea water, which is heavier? 2. Which is easier to freeze? Sea water

Density is the relationship between _______ and ________. A substance with a _____ (lower, higher) density can float on water. When water freezes, its density _______. (decrease, increase) mass volume lower decreases Para 4 density

Para 5 Heat Capacity Read the paragraph, discuss in group of four and translate it into proper Chinese. Suggested answers: 热容量是一种物质升高一摄氏度所需的能量。水的热容量 相对较高。水可以吸收或释放出大量的热量而其温度不会 变化很大，因此能创找一个稳定的环境。 大多数动物和 植物对温度的大的或突然的改变非常敏感，因此，海洋就 给动植物提供了一个安全而舒适的生活环境。由于海水的 吸热和释热的作用，从而使地球温度保持平衡。 Can you think out an example to show the function of the high heat capacity of water?

Para 6 Ocean Motion Changes in salinity & ___________ affect water’s __________ Dense water _______, _____ _______ water is pushed to the surface. temperature density sinks less dense What causes sea motion? How does the water move?

Significance/importance of water to nature Para Closing paragraph Try to add a subtitle for it !

properties What properties have we just learned? dissolvability salinity density motion heat capacity consolidation

Here are some phenomena( 现象 ). What property of water is each of them related to? 1.The coastal areas are often neither too hot nor too cold. High heat capacity 2. People swimming in the Dead Sea float; they can even read a paper while lying on their back in the water. Salinity and Density

3. Ice floats on water. Density high heat capacity Motion 4.Irrigate( 灌溉 ) in winter can help raise the soil temperature. 5. We build Three Dams Power Station( 三 峡水电站 ) to produce electricity.

Suppose you are one of the main properties of water (dissolvability, salinity, density, heat capacity, ocean motion …). You think you are the most important and have the greatest effect on life. Try to persuade others by describing: 1) What you are. 2) What affects you. 3) What you are made the most of by human beings.

Hello, I am the “ motion”. I am influenced by density and temperature. If the density and temperature of ocean change, the dense water sinks and less dense water is pushed to the surface, thus I come into being. I can help carry the nutrients around to provide enough energy for the marine life. People usually make use of me to produce electricity. but if I am not happy and cannot be used properly, I could be rather dangerous and cause a great deal of damage and deaths to people. So everybody, treat me with respect and carefulness.

Suppose you are one of the main properties of water (resolvability, salinity, density … ). You think you are the most important and have the greatest effect on life. Try to persuade others by describing: 1) What you are. 2) What affects you. 3) What you are made the most of by human beings.