高中英语必修四.pptx
VSStep1 Lead-in big and beautifulfresher,healthier,taste better第1页/共32页 to improve the output of the crops fertilizer herbicide pesticide 第2页/共32页natural fertilizer from animal wastechemical fertilizerHow many kinds of fertilizers do farmers use?第3页/共32页 Which kind do farmers use when they are doing organic farming?第4页/共32页Chemical fertilizers第5页/共32页 green food organic food 第6页/共32页Chemical or Organic Farming?第7页/共32页D.Long-term use of chemical fertilizerscan cause damage to the land and peoples health.B.Farmers and customers turn to organic farming.C.Other methods to keep the soil fertile.Step 2 Reading 4mA.Problems caused by chemical fertilizers.Task 1 Skim the passage and match the main idea with each paragraph.P1.P2.P3.P4.The main idea of this passage:_can cause _,so _ is becoming more popular.chemical fertilizersmany problemsorganic farming第8页/共32页 1.Why are chemical fertilizers so popular in farming today?2.What problems can be caused by using chemical fertilizers?3.What is organic farming?And what are the advantages of organic farming?4.What methods do the organic farmers use to keep the soil fertile?Task 2 Read the passage carefully and answer the following questions第9页/共32页1.Why are chemical fertilizers so popular in farming today?Many farmers welcomed them as a great way to stop crop disease and increase production.Paragraph 1第10页/共32页Chemical fertilizer damage the land or the water supplydamage peoples healthGrow too fast to be full of nutrition2.What problems can be caused by using chemical fertilizers?第11页/共32页What problems can be caused by using chemical fertilizers?There are three problems.First,they can damage as well as.They also stay in the and.In addition,grow too fast to.first;second;finally;last but not least,etc.Para 2第12页/共32页 There are three problems.First,they can damage as well as.They also stay in the and.In addition,grow too fast to.Tips:connectives（过渡（过渡词）词）and transitional phrases（过渡词）（过渡词）for developmentParagraph 2第13页/共32页advantages3.What is organic farming?What are the advantages of organic farming?Make the soil richer in minerals and more fertileHelp crops grow strong and healthy keep the air,soil,water and crops free from chemicals.(Environment-friendly)Paragraph 3Farming without using any chemicals.第14页/共32页It is obvious that An advantage of organic farming is that What is even more important is that That is the reason why many farmer have turned to organic farming.organic farming means growing crops without using any chemicals.the farmers focus on keeping their soil rich and free of disease.it can keep the air,soil,water and crops free from chemicals.第15页/共32页 The methods to keep the soil fertile1.using natural waste from animals as fertilizer.2.changing the kind of crop in each field.3.planting crops to use different levels of soil.4.planting grass between crops to prevent The same goal:_ to grow good food and to avoid damaging the environment or peoples health.Paragraph 3 and 4第16页/共32页para1:A new discovery of scientists.para2:Several problems caused by using chemical fertilizers.para3:The advantages of using organic farming.para4:Some methods to keep the soil fertile.The structure of this passagePara1 TopicPara2 ProblemsPara3 AdvantagesPara4 Several methodsillustration（阐明）comparison conclusionThe type of the article is_exposition（说明文）第17页/共32页Over the past half century,have become very common.welcomed them as a way to.Recently,however,we have been finding that they can cause damage to,even,to peoples health.What are some of the problems caused by?First,Second,Last but not least,With these discoveries,are beginning to turn to.The following words may help you.第18页/共32页Problems：1.cause white pollution2.easy to be broken3.difficult to break down4.do harm to the environment and peoples healthAdvantages：1.can be recycled and reused 2.save resources 3.cheap4.protect the environment第19页/共32页 Over the past half century,plastic bags have become very common in our daily life.We welcomed them as a convenient way to carry goods.Recently,however,we have been finding that they can cause damage to the environment,even worse,to peoples health.第20页/共32页 What are some of the problems caused by plastic bags?First,people often leave plastic bags here and there,making white pollution.Second,it takes a long time,more than 100 years,to be exact,to break up.Last but not least,when heated,plastic bags can produce something harmful,which can build up in our body and eventually lead to cancer or other illnesses.第21页/共32页 With these discoveries,we are beginning to turn to cloth bags.They can be used many times.People can save a lot of source in this way.It is also a good idea to make some by ourselves,which is interesting.Lets use cloth bags in our daily life instead of plastic bags,not only for the environment protection,but also the sake of our health.第22页/共32页Step 3 Supplementary readingPassage A What is mainly discussed in this passage?Why organic food cost moreLower yieldsRising labor costsHigh demand第23页/共32页Reasons Why Consumers Should Buy Organic FoodPassage Bhealthy and safe builds strong future generationskeeps our water cleanresults in less soil erosionoffers outstanding flavorbecoming more affordablereasonsContinually purchase organic foodYour purchases now make a difference in the long run.第24页/共32页Step 4 Making a Dialogue(Pair work)Situation:You are a farmer and your partner is the customer,who doesnt know much about the organic food.You are persuading the customer to buy your organic food that is healthy and safe but more expensive.第25页/共32页Making a Dialogue(Pair work)FarmerFarmerCustomerCustomerIts better to This is good value becauseThe advantages areIts more expensive butYoull taste the difference whenIts a great pity thatId preferbecauseI dont like becauseIf I have a choice Ill chooseWhats the advantage of?Id rather第26页/共32页Designing a poster Designing a poster Design a poster to advertise the organic food youre selling.Step 5 第27页/共32页How to write a posterHow to write a poster Buy the Best Vegetables Here We only sell green food!Best choice at best prices!Look1.no chemical fertilizer23You and your family will stay fit and healthy if you eat green food.Main headingThis explains that you sell green food.Reasons to buy:Reason 1:Reason 2:Reason 3:(Conclusions)Why it is good value.brief,persuasive,vivid nice,creativefour partsContentLanguageDesign第28页/共32页If you want to be healthier and fitter you should eat organic food.Eat organic food to become healthy and fit.You ll find the taste of organic food more delicious than ordinary vegetables and fruit.Organic food tastes more delicious.第29页/共32页Evaluation After this lesson,I am able to do the following things.VerywellQuitewellOKAlittleLittleExplain what organic farming isUse the correct phrases to try to persuade somebody to do somethingDesign a poster in EnglishThink local,choose organic Percentage 95%85%75%60%40%第30页/共32页 Use the information you have learnt today to write a report about organic farming and organic food.Homework第31页/共32页感谢您的观看！第32页/共32页
