2015-2016学年高中英语人教版必修四课件：UNIT 2 PERIOD 4 USING LANGUAGE .ppt

1、 Unit 2 Working the land Using language231.Master the following new words,phrases and sentences in using languageproduction,bacteria,pest,nutrition,discovery,soil,rootregret,reduce,regretbuild up,keepfree from,lead to,focus on,in additionSome organic farmers prefer planting grass between crops to pr

2、event wind or water from carrying away the soil2.Learn the advantages of organic farming.本课首先观看嘉世有机农业视频，引出本节题目“化学耕作还是农业耕作”。进而讨论化学耕作和有机耕作的概念。化学耕作的弊端是什么？为什么农民转而开始有机耕作？有机耕作通过什么方法来保持土地的肥沃？然后让学生听课文录音，了解短文的主旨以及各段的大意。最后讲解短文的语言点。最后通过改写的短文加深对本文的了解。讲解农业耕作是配有相关的视频，有助于学生理解。总结概括文章和段落大意，提高学生的理解和表达能力。听课文录音有助于学生听力水

3、平的提高。ReadingCHEMICAL OR ORGANIC FARMING?What can we harvest?No pains,no gains.嘉世有机农业Add fertilizer into the soilHow can farmers make the plants grow well?How many kinds of fertilizers do farmers use?natural fertilizerorganic farmingchemical fertilizerchemical farmingTwo kinds.Discussion:Which kind o

4、f farming is better?BetterLets learn more about chemical and organic farming!Listen to the tape carefully.using language readingorganic farming is becoming more popular.The main idea of the text:Long-term use of chemical fertilizers can cause damage to the land and peoples health.Problems caused by

5、chemical fertilizers.The main idea of each paragraphP1.P2.Farmers and customers turn to organic farming.Other methods to keep the soil fertile.P3.P4.1.Why are chemical fertilizers so popular in farming today?A.Because they are cheap.B.They are a good way to stop crop disease and increase production.

6、C.They can cause damage to the land.D.They do good to peoples health.Paragraph IChemical farmingadvantagesproblemscausestop crop diseaseincreaseproductiondamage thelandby killing the helpful bacteria and pests as well as the harmful ones.affect cropsby staying in the ground and underground water for

7、 a long timelead to cancer/illnessesby building up in peoples bodies over timehave lessnutritionby growing too fastParagraph 2Organic farmingNatural waste from animalsMake the soil richer in minerals and more fertileA healthy soilReduce diseases in cropsHelp crops grow strong and healthyParagraph 3O

8、rganic farmingmethodsadvantagesuse natural wastemake the soil richin mineralschange the cropput minerals back into soil,makingplant crops with different rootsuse different levels of land plant grass between cropspreventfrom,a natural fertilizerParagraph 41.Which statement is WRONG according to the t

9、ext?A.All crops are organic.B.Recently,the term“organic farming”has gained another meaning.C.All farmers use fertilizers.D.Scientists believe some chemical fertilizers are better for people.Read again and choose the best answer.D2.Which is not the reason why organic farmers prefer natural waste from

10、 animals?A.It can keep the food free from chemicals.B.It can keep the air,soil and water free from chemicals.C.It can kill harmful pests.D.It can make the soil richer in mineral.C3.What is the advantage of using chemical fertilizers?A.Leaving chemicals in the ground for a long time is good for water

11、 supply.B.They can get the soil exhausted.C.They can kill helpful bacteria.D.They can kill harmful pest.D4.The organic farmers do the followings except _.A.adding fertilizers which is rich in mineralB.changing crops every two or three yearsC.planting seeds in different layers of the soilD.planting g

12、rass between crops to prevent the soil from being blown awayA1.What is“organic farming”?Answer the questions.It refers to crops growing with natural rather than chemical fertilizers.2.What do organic farmers prefer to use as fertilizer?Natural waste from animals.Because peas and beans can put minera

13、ls back into the soil,making it rich and healthy and ready to grow more wheat or corn.3.Why do organic farmers grow peas or soybeans after corn or wheat?4.What is the main goal for using organic farming methods?To grow good food and to avoid damaging The environment or peoples health.No use of chemi

14、cal fertilizers Away from industrial areas Away from dirty water supply No air pollutionA summary of organic farming:Fill in the blanksMany farmers welcome _ fertilizers because they are great way to stop crop disease and increase _.But these chemical can _ to illnesses.So farmers began to turn to _

15、 farming.They _ on keeping their soilrich and _ of disease.Organic farmers often prefer using _ waste of animals as fertilizer.This keepsthe soil free _ chemicals.There are many methodsto keep the soil _.The methods have the same goal:to grow good food and avoid damaging the _or peoples health.chemi

16、calproductionfocusfreenaturalfromfertileenvironmentleadorganic1.These chemicals in the food supply build up in peoples bodies over time.Language PointsHard working conditions build upcharacter.build up 增强;建立;开发艰苦的工作条件能磨练人的性格。2.Many of these chemicals can lead tocancer or other illnesses.All roads le

17、ad to Rome.lead to 导致；造成条条大道通罗马。3.They focus on keeping their soil rich and free of disease.focus on:集中(注意力,精力等)于You should focus your attention onyour work.把注意力集中在你的工作上。4.This also keeps the air,soil,water and crops free from chemicals.4.You must take care to keep the wound free from the dirt.keeps

18、 free from/of:使免受(影响,伤害等);使不含(有害物)你必须照顾好伤口，免受灰尘的伤害。5.reducev.减少,降低e.g.公司尽力通过减少花销来提高利润。The company tries to increase profits by_.今年我们已经减少了业务开支。We _ expenses this year.reducing costshave reducedExpressions1.化肥2.对造成损害3.洗掉某物4.导致;造成(后果);通往5.逐渐增强,建立6.另外(还有)7.使免受(影响);8.集中(注意力、精力)于9.每隔几年10.避免做chemical ferti

19、lizerscause/do damage towash offlead tobuild upin addition(to)keepfree from/offocus onevery few yearsavoid doingExerciseswash off,lead to,build up,in addition(to),keepfree from/of,focus on,avoid doing1.His mistakes _ his failure.2.These chemicals in the food supply_ in peoples bodies over time.3.All

20、 roads _ Rome.4.Please _ your mind _ the following problem.5.Children should _ violence.led tobuild upfocus onlead tobe kept free fromin additionwashing offavoid meeting6.He likes basketball,_,he likes football.7.Little Tom stuck to _ the mud _ his shoes by himself before he came in.8.I tried to _(meet)him because he always bores me.HomeworkWrite an article about future farming.