人教版高中英语Unit19Modernagriculture教案.doc

Unit 19Modern agriculture.Teaching Goals:1.Talk about modern agriculture and the effects it has on peoples life.2.Practise giving advice and making decisions.3.Use “It” for emphasis.4.Read statistical graphs.5.Write a plan for a vegetable garden.Teaching Time:Five periods.Background Information:1.An American Small FarmLast year,at harvest time,we visited the Steenhoek farm,which is 2 200 mu,or 340 acres.Typical family farms are run entirely by family members,with every member playing a vital part in the operation.Both of these families are descendants of Dutch immigrants who settled here over a century ago.The Steenhoek farm supports 3 generations.The family of Mr.and Mrs.Steenhoek includes three children and 2 grandchildren.As we will see,this family is an excellent example of hardworking,experienced farmers who stay on the land not purely because of profit,but because they are living a life-style that satisfies them.Sixty percent of the Steenhoeks acres are devoted to pasture land,on which they raise 120 beef cattle.The rest of the land is used for growing corn.Fifteen years ago,the American farm economy was booming.Farmers could specialize,raising one crop,or one type of animal.Today,with an uncertain farm economy,such an idea is considered foolhardy,and diversifying is one way that farmers can lesson their risk of loss.For example,if weather affects the size of a crop,the sale of the livestock will make up the difference.If the animals are plagued by disease,at least there is grain to take to market.Kendall Steenhoek,Simons eldest son,divides his time between running this machine shop and farming zoo acres of corn.He attended a community college in Iowa for two years to study diesel mechanics.Then he opened this repair shop for farm machinery.Kendall also plants and harvests over 30 000 bushels of corn each year,but it is the income from the repair shop that has enabled him to stay within the farming community.The heavy equipment used on the farms today is in constant need of maintenance,and requires precision tooling for repairs.By far,the most impressive and certainly the most costly piece of farm equipment used on a small farm is a harvesting machine called a combine,which can cost up to $100 000.This type of machinery is what makes the American farm so efficient.With a combine,one man and his family can harvest an entire crop of a 500 acre farm in two weeks.The value of the combine is that it performs several functions.As it moves through a field of corn,this sophisticated machine cuts the stalk,plucks the ear,discards the stalk,shucks the corn kernels off the ear and deposites the kernels in a storage bin in the back.Then,a spinning device in the rear of the combine shreds the husks and shafts and scatters them across the field,to serve as mulch,cutting down on the possibility of soil erosion from winter rains.The machine is even more amazing when you think that it has been in use on American farms for only one generation.2.GenesEvery living cell contains genes.They are too small to be seen in a microscope,but they are vitally important.Each set of genes in the body contains all the instructions needed to make a human being.Some genes determine hair color.Some determine the shape of a nose.Some genes help determine your height and even your weight.Genes are made of a chemical called DNAthe letters stand for deoxyribonucleicacid(脱氧核糖核酸).In the early 1950s,two scientists,Francis Crick and James Watson,figured out how the parts of DNA fit together.Once scientists understood this structure,it became possible to take pieces of DNA apart and put them together in new ways.New kinds of genes could be made in this manner.Scientists have studied the genes of many plants and animals.They have worked out which genes affect the color of a tomato and the stickness of its skin.Working out which genes determine which features is called genetic mapping,scientists have begun the Human Genome Project,an ambitious effort to map all the genes in the human body.Some genes may be effective.For example,something might be wrong with the gene that makes blood clot(凝聚).An individual born with this defective gene could suffer serious hemorrhages(出血)or even bleed to death because his or her blood fails to clot.If scientists ever learn how to map all the genes in our bodies,they could determine whether or not an unborn child has any defective genes.They might even discover how to treat these genes before the child is born.The First PeriodTeaching Aims:1.Improve the students speaking ability by practising giving advice and making decisions.2.Enable the students to master the expressions of giving advice and making decisions.3.Get the students to learn more about agriculture.Teaching Important Points:1.How to express oneself,using what is learned or given.2.How to advise sb.to do something and how to make decisions.Teaching Difficult Points:1.The usage of some expressions.2.How to improve the students listening ability.Teaching Methods:1.Listening some materials to improve the students listening ability.2.Discussion to let the students express themselves freely.3.Group work or pair work to give every student a chance to express themselves.Teaching Aids:1.a tape recorder2.a projector and some slides3.a computerTeaching Procedures:step .Greetings and RevisionT:Good morning,everyone.Ss:Good morning,teacher.T:Sit down,please.In this class,Ill check your homework first,Wang Ping,read your homework to us,(The teacher checks the students homework and have a discussion with the students about the mistake Wang Ping made.Let the students have a clear understanding and correct it.)step .Preparation for listening and speakingT:Today,were going to learn a new unit,Unit 19,Modern Agriculture(Teacher writes the following on the blackboard:Unit 19 Modern agriculture,the First Period).First,lets learn the new words of this period.Look at the screen:New words:produce n.产量、产物、农产品effect n.结果、影响、作用dike n.堤坝；排水沟drought n.干旱leader n.领导者lead v.领导、带领cane n.细长的茎、藤条sugar-cane n.甘蔗tobacco n.(烟草)制品；抽烟local adj.地方的、当地的(Teacher asks one student to read the new words,then corrects the mistakes the student made.)Step .Warming upT:Please turn to Page 32.Lets do Warming up.(Teacher shows the graphs on Page 32 on the screen.)Look at the two graphs and discuss the questions on Page 32.You can do it in pairs or groups.In a few minutes,Ill ask some students to talk about them.(Students begin to discuss the questions.And teacher goes and joins them.A few minutes later,teacher says the following.)T:Are you ready?Who can give us a talk about the first topic?SA,how are peoples eating habbits changing over the years?SA:From the first graph,we can see that the eating habits of the people in our country have changed greatly.Before 1949,they had not enough to eat and often went hungry.Once natural disasters happened,a great number of people would die of hunger.Before the reforming and opening to the world,grain was still a big problem.People mainly lived on corn and few kinds of vegetables.Since the 1980s,especially the 1990s,peoples eating habits have greatly improved.People can eat whatever they want.More and more people eat less grain,more meat and eggs and so on.More and more people turn their eyes to meat,eggs,milk and all kinds of green vegetables.T:Why do you think this happens,SB?SB:It is all because of the Partys good policies.T:Very good.It is true and everyone can see that.How has agricultural produce changed during the first half of the 1990s?And what do you think caused these changes?SC:From the first half of the 1990s,scientists started to develop new techniques to increase agricultural production without causing damage to the environment.Especially the new technique, “GM”,has made agricultural production increase continuously.Scientists develop new kinds of seeds,better cows,pigs,sheep as well as fish.It is the new techniques that make all this possible.T:Do you agree with him,SD?SD:Yes,I do.And I want to give an answer to the three question.T:Good,please say that.SD:With the changes in peoples eating habits,agriculture as well as nature will have to change,too.People are eating more meat and milk.That is to say,they need more fish,pigs,sheep and cattle as well as poultry.To feed these animals,we need more grain,especially more grass.To protect our environment,the ways to raise animals have changed.With the development of modern science and techniques,some of the fields are not needed to produce more food.We can grow grass,flowers etc.on them.Less farmers are needed and they can do other kinds of work.Step .ListeningT:So much for the discussion.Next well do listening.The passage youll listen to is about farming.It tells us about farming of all countries in early times and protection of nature and environment.Listen to the tape carefully and do the exercises concerned.Now,read the requirements,please.(Students read the requirements.)Now do you know what youll have to do after listening to the passage?(Ss:Yes.)During listening,Ill play the tape three times.After listening for the first time,you can leave over the ones you are not sure about.You can do them when I play the tape for the second or the third time.Check your answers with your partner after listening.Are you clear?(Ss:Yes.)(At last,teacher shows the answers on the screen.)Step .SpeakingT:Now lets do speaking.This part says that a group of farmers in your area have been given a large piece of land.The villagers together with the village leader have to decide how to use the land.Work in groups of five students.Each group member will play one of the roles.Prepare role cards,discuss the problem and try to make a decision.Before discussion,who can give us some useful expressions about giving advice and making decisions?Giving advice:SE:My advice would be.I advise you to do.SF:I think you ought to.You.d better.SG:If I were you,I would.I would advise you.SH:I dont think you ought to.Making a decision:SI:In my opinion,we shouldI think/believe you shouldSJ:I dont think it is necessary to do sth.We must decide.SK:I hope we can make a decision.(Teacher writes all the expressions above on the Bb.)T:Now lets have a discussion,using the expressions on the blackboard later,Ill ask some students to act it out.Sample diaolgue:Savillager A;Sbvillager B;Scvillager C;Sdvillager DSethe village leaderSe:As we all know,we are given a large piece of land.Ive got all of us here to have a discussion and decide how to use the land.Please give us your advice.Sa:I advise we should grow corn on this piece of land.Its large and flat and machines can go up and down it,so we can spend less time and get more corn.A lot of money can be made after selling the corn.Sb:I think we ought to build a farm there and raise pigs or cows with the grain we harvest.So we can make more money.Sc:My advice is that we should turn it into a garden,and grow flowers there.Then we can sell the flowers.There is nobody here selling flowers.So I think our business will surely be good.Besides,sometimes selling grain or meat is hard,for the price could be too low.Sd:I think wed better design it like this:We build a building of a few floors.In each floor,we can raise one kind of animals.With their wastes,we can raise fish or grow vegetables on the top or in the space which faces the sun.We can also grow mushrooms in the dark places.We can use one quarter of it to do this and build a garden on one quarter so that people can enjoy themselves here.Half of the rest grow flowers to sell and for the other half we can grow grass on it so that our environment will be better.Sa:Thats a good idea.But it will need a lot of money to do this.I hope we can make a decision today.Se:We must make a decision.My opinion is that we do as SD said.Any other opinions?Sb and Sc:I agree with you.Step .Summary and HomeworkT:In this class,weve talked about two statistical graphs and listened to a passage.We have also talked about how to use a large piece of land,using some expressions of giving advice and making deicisions.These expressions are:“”(Pointing to the blackboard.)After class,choose a subject as you like with your pratner and have a discussion,using the expressions on the blackboard.Thats all for today.Class is over.Step .The Design of the Writing on the BlackboardUnit 19Modern agricultureThe First PeriodGiving advice:My advice would be.I advise you to do.I think you ought to.Youd better.If I were you,I would.I would advise you.I dont think you ought to.Make a decision:In my opinion,we should.I think/believe we should.I dont think it is necessary to do sth.We must decide.I hope we can make a decision.Step .Record after Teaching_The Second PeriodTeaching Aims:1.Enable the students to learn something about modern agriculture from the text.2.Enable the student to master the new words and expressions in the text.3.Get the students to have the ability to grasp the general idea of an passage as fast as possible.Teaching Important Points:1.How to improve the students reading ability.2.How to get the students to master the new words and expressions of the text.Teaching Difficult Point:How to improve the students reading and writing ability.Teaching Methods:1.Discussion to raise the students interest in agriculture.2.Ask-and-answer method to help the students understand the text better.3.Free talk to improve the students speaking ability.Teaching Aids:1.a tape recorder2.a projector and some slides3.a computer for multimedia useTeaching Procedures:step .Greetings and RevisionGreet the whole class as usualT:At the end of the last period,I asked every one of us to join in a discussion.Now Ill ask a group to repeat the discussion.Who will act it out for us?Wang Hong,act it for us with your group,will you?Wang:Yes.(Teacher asks two groups to repeat their discussion before the class.)step .Preparation for ReadingT:So much for revision.Please turn to Page 113.Lets learn the new words and expressions together.Li Ming,read the new words and expressions of this period,please.Begin with the word“arable”and end with the word “soil”.(Teacher and the students learn the new words and expressions together.Teacher corrects students mistakes in pronunciation and gives simple explanations of some words if necessary.)T:Are there any students coming from the countryside in our class?Ss:Yes.A lot of us students are from peasant family.T:Have you ever worked in the fields,Wang Fei?Wang:Yes.I often work in the field with my parents.I can do a lot of farm work.T:Have you ever heard of anything about farming in the past?Ss:Yes,I have.T:Now turn to Page 34.Lets do pre-reading.Discuss the questions.Group work.Write your answers on a piece of paper.(After a few minutes.)T:Are you ready?(Ss:Yes.)Who would tell us something about traditional and modern farming?SA:In the past,farmers grow crops in the traditional way:Use cattle to plough the field;farmers work in the field most of the day all year round,but they could not produce enough food for the whole population.Now they grow crops in the modern way.They use modern techniques in their fields,such as chemical fertilizers,greenhouses and so on.T:Who would answer the second question?SB:Ill try.The advantages are:chemical fertilizers,electronic pumps and other advanced technology are used.Farmers can spend less time on farms and much more grain is produced.The disadvantages are:the air,the water and the soil round us are more or less polluted.Sc:Ill say something about other changes that have taken place on farms in the last 100 years.In the past,we depended on heaven and we could do little when natural disasters happened.Now,we can do artificial rainfall.GM makes better seeds possible.In the same fields,better seeds can give us much more grain.Besides,all kinds of scientific ways of farming are used in farming.Farmers in our country are becoming richer and richer day by day.T:Very good.Step .Fast ReadingT:Now read the text fast and then answer the questions on the screen.1.When was more advanced technical information was brought in from abroad?2.What is important for future agriculture?What should future agriculture depend on?3.What does“which”refer to in the last two lines?(After a few minutes.)T:Are you ready?Ss:Yes.T:Please give us the answers to the questions.SD:In the 1980s,more advanced technical information was brought in from abroad.SE:Both food production and taking care of the environment are important.And future agriculture should depend on high technology as well as traditional methods.SF:I think taking care of the environment is more important.Because we have only one earth.Sa:In the last two lines,“which”refers to“golden rice”.T:What is the other name of “golden rice” in the text?Sa:GM rice.Step .ReadingT:Now read the text again and answer the questions in Post Reading.If you are not sure about your answers,have a discussion with your classmates.(After the students discussion)T:Please turn to Page 35.Lets answer the questions.SH,give your answers to the first five questions.SH:They are:1.D2.A3.C4.C5.CT:Is he right?Ss:Yes,he is right.T:Now lets do Part 2.SI:I want to change apples.I want them not only to grow bigger and more delicious,but also of the same size.Because some of the apples now are smaller and not delicious and the apples of the same size are popular in the market.SJ:I want to change f