【精品】高中英语(人教大纲)第二册下：Unit13Thewaterplanet(第一课时)

1、Unit 13The water planet .Brief Statements Based on the UnitAs we all know,the earth is an ocean planet and 99% percent of the living space on earth is inthe oceans.It is water that makes the ocean such a great place to live in.This unit mainly deals withthe properties of water and how the properties

2、 of water make the ocean become so important.Welearn this unit to help students not only know about the properties of water,but also learn how touse water in a good way.Besides,we learn this unit to let students realize the importance ofprotectingwater.Of course,it is necessary forstudents to master

3、 the importantphrases andsentences in the unit.Meanwhile we should review some important usage of Modal Verbs. .Teaching Goals1.Talk about water and the ocean.2.Practise communicative skills.3.Review Modal Verbs.4.Write an explanation paragraph. .Background Information1.What Lies under the Blue Wate

4、r?Just like the houses we live in,the ocean has several “ floors ” or layers.Different fish live on different layers and are neighbours,though not always friendly ones!The oceans top layer is the sunlit zone( 透光层 ).It goes down to around 200 meters below water.This layer is warm and bright.It is als

5、o home to most plants and fish.Many fish in this layer are streamlined,so they can quickly swim from danger and catch food.The twilight zone(弱光层 ) is the next layer and is from about 200 to 600 meters below water.Almost no plants grow here.Many animals in this zone swim up to the surface at night to

6、 feed,and move into deeper waters during the day.They also eat each other,so many of them have sharp teeth and very big mouths.Many fish in this zone donthave a streamlined body because they lie and wait for prey tocome to them.Below the twilight layer is the midnight zone(无光层 ).It is from 600 meter

7、s to the bottom ofthe sea.The water is cold and completely dark.No plants live here but many small animals can.Many animals in the twilight and midnight zones produce their own lights.The angler-fish(琵琶鱼 ) is one of them.It has a beautiful light on its head to attract prey!Maybe you have seen one of

8、 the coolest films FindingNemo (海底总动员).Do youremember Marlin,Nemo s father,“ borrowed” light to help Dory read?That wasnta flashlight,it was a fish!They also use light to frighten enemies and to“talk ”with each other.12.WaterA family of six needs over 20 gallons of water a day,just for basic drinkin

9、g,cooking and keeping clean;but only one in three of the world s households has a water supply in the home.Most others get their water from rivers,lakes springs or holes in the ground,or,in town,from stand-pipes shared with hundreds of other families.Throughout the world s poorest countries women da

10、mage their health and lose hours of every day carrying huge containers of water up to 44 lbs in weight often from sources several miles away.All too frequently they bring home sickness or death,as well as water.Untreated water,which may have come from a muddy hole shared with cattle,can be lethal,es

11、pecially for young children.To sink a well or pipe water from a natural spring,and maintain the system afterwards,people need access to land with a water source,to capital,equipment and technical know-how.In towns they may need to lobby the local water authority to repair or extend existing systems.

12、Water is precious,and access to it gives power to landowners with wells on their land,or to country controlling major international rivers.The demands on the earths water resources are growing rapidly,partly as a result of population growth,but even more because industry now uses such huge quantitie

13、s it takes 100 000 gallons to produce a car. .Teaching Time:Five periodsThe First PeriodTeaching Aims:1.Learn and master thenew words and the useful expressions of this part.Words:cube,sailor,disadvantages,entertainmentPhrases:come up with,happen toUseful expressions:The water is being used to/for W

14、e should/could If we we canIt would be better 2.Learn something about water by doing experiment.3.Do some listening.4.Improve the studentsspeaking ability by talking.Teaching Important Points:1.Make the students be free to talk about water.2.Improve the studentslistening ability by listening.Teachin

15、g Difficult Points:1.How to finish the task of speaking.2.How to improve the students listening ability.Teaching Methods:1.Listening-and-answering activity to help the students go through with the listening material.2.Individual,pair or group work to make every student work in class.Teaching Aids:1.

16、the multimedia2.the blackboard23.an empty glass,a bottle of water and a bottle of vegetable oilTeaching Procedures:Step Greetings and Lead-inT:Hello,everyone.Ss:Hello,teacher.T:Attention,please.As we all know,every year during the Spring Festival and Lantern Festivalin our country,people like to see

17、 the lion dance and guess the riddles.Do you like to guess theriddle,then?Ss:Yes.T:OK.Now I have a riddle.Please guess it.(Teacher uses the multimedia to show the riddle on the screen.)It s very important to all the animals and plants.It s also important to human beings.It s liquid at room temperatu

18、re.Every day you keep in touch with it.You cantlive without it.(a thing)T:What s it?Ss:Its very easy.Its water.T:Yeah,today we will talk about water.Now please tell me what you know about water.S1:Water is used to drink.S2:Water can be used to water the flowers.S3:I think water can be used to make e

19、lectricity.Step Warming upT:Thank you for your ideas.Next we will make some interesting experiments.Maybe you can learn more about water from the following experiments.Li Lei,would you like to come here to help me?S4:Id love to.T:Now,look at Li Lei and me.We will begin.You should watch the experimen

20、t carefully andtry to tell me what happens and why.(Teacher puts a bottle of water,a bottle of vegetable oil and an empty glass on the desk.) T:Li Lei,pour some water and some vegetable oil into the empty glass.Other students,pleasewatch carefully.(A few seconds later.)Ss:Fantastic!The liquid in the

21、 glass has become two parts.T:Try to describe it in detail.S5:Let me try.The part above is vegetable oil and the part below is water.But I dontknowwhy.T:Good question.Who d like to answer his question?(Nobody answers his question.) T:Perhaps it is a little difficult to answer it immediately.Now you

22、can have a discussion aboutthe reason for it,using what you have learnt in physics.(Teacher lets students discuss in groups of four.A few minutes later,teacher checks their answers.)T:Who wants to explain the phenomenon?3S6:I think water is heavier than oil,so vegetable oil is on the top of the wate

23、r.T:Who has different ideas?S7:I think we should say that the density of water is higher than the density of vegetable oil,so the result formed.S8:What s the meaning of “ density” ?S9:“ Density ” is “密度”in Chinese.T:Do you agree with the reason for it?Ss:Yes.We agree with the idea.T:As we know,if we

24、 pour milk and water into one glass,we cant tell where water is and where milk is.But just now we poured oil and water into one glass,it is so different now.Do you know why?Ss:Because oil cantdissolve in water,but milk can.T:Very good.Let s make a summary about the experiment.If we pour vegetable oi

25、l and water into one glass,the liquid will become two parts because oil cant dissolve in water.Since the density of water is higher than vegetable oil,vegetable oil will be on top of the water.Is that clear?Ss:Yes.T:Would you like to watch another experiment?Ss:Id love to.T:OK.I ll perform the next

26、experiment by myself.Look at me.I have a glass of water.Now Illcover it with a piece of thick paper.Attention,please.(Teacher puts one hand on the paper and turns the glass upside down.Then teacher slowly takes his/her hand away from the paper.)T:What can you see?Ss:The piece of paper doesntfall and

27、 the water in the glass doesn tflow.T:Yes.You are right.Now you are given a few minutes to have a discussion about the reasonfor it.(Teacher gives students a few minutes to discuss,and then checks their answers.)T:Who can tell us the reason why the piece of paper doesn tfall and the water doesn tflo

28、w? S10:I want to have a try.When the glass of water covered with a piece of paper is turnedupside down,the pressure from air to the piece of paper is bigger than the pressure from the water in the glass to the piece of paper.So the paper wontfall and the water won tflow.T:Excellent!Thank you for you

29、r explanation.I am very glad to see that you are all interested in making experiments.After class,you can carry out another two experiments on Page 17.When you perform them,try to describe what happens and why.OK?Ss:OK.T:Now,let s look at a picture.(Teacher shows a picture on the screen.)T:What can

30、you see?Ss:There is a river in the picture,but it s very dirty.T:Anything else?4S11:There are some plastic bags and empty tins on the surface of the river.T:Yes.We all know water is important to human beings and all the animals and plants.Unfortunately water is being polluted now.What do you think w

31、e can do to protect the water on our planet?(Teacher gives students enough time to prepare.When they prepare,teacher goes among the students to help them to express their ideas correctly.)Sample answer:To protect the water on our planet,I think we should save every drop of water and stop throwing ru

32、bbish into water.Besides,we should try our best to help the people around us realize the importance of using and protecting our water.Step ListeningT:Next,let s do some listening.Turn to Page 18 and look at the Listening part.You can listento the famous poems about life on the ocean.Listen carefully

33、 and write down some key wordswhen you listen.Before you listen,let s learn two phrases first.Look at the blackboard.1.happen toIf anything happens to the machine,please tell me.e up with(Teacher writes them on the blackboard and begins to explain them.)T:Now listen,please.(Teacher plays the tape fo

34、r the first time.Then play it for the second time.During this time,teacher may pause for students to write down the information.Play some parts of the tape one more time if necessary.Finally teacher checks the answers with the whole class.)Step SpeakingT:In our daily life,water can be used in differ

35、ent ways.Now well talk about the ways in which water can be used.Look at the pictures on Page 18.The six pictures mean six different ways to use water.You can choose one of the pictures to discuss the importance of using and protecting our water,and then try to use some sentences to describe the pic

36、ture you choose.If you like,you can make a dialogue with your partner about the picture.When you discuss,you may use the questions on the screen to help you.1.How is the water being used?2.Is this a good way to use water?3.Why do we use water in this way?4.Who benefits from using water in this way?5

37、.What are some disadvantages of using water in this way?(Teacher shows the questions on the screen by multimedia and gives students enough time to discuss and prepare.)Suggested answers:(Picture 1)We can use water to make electricity,which can give us light and make us feel warm.I think it is a good way to use water.(Picture 3) Water has a lot of usages and home use is the commonest one.Every day we must drink enough water.In addition,we need a lot of water,just for cooking and keeping clean.Water can help us to keep healthy.But if the waste water from home use is poured into ri