Unit+5+Working+the+Land+Using+Language+(II)+课件【知识精讲精研】高中英语人教版（2019）选择性必修第一册

Unit5Period4UsingLanguage(Ⅱ)EvaluatechemicalfarmingandorganicfarmingDoyouknowwhatsubstanceisputinthesoiltomakeplantsgrow?新课导入Itisfertiliser.1.能通过阅读语篇了解化学农业与有机农业的区别及其优缺点，学习议论文的结构；2.写一篇文章来表达你对化学农业或有机农业的看法。课堂学习Pre-readingLookatthetitle,anddoyouknowwhatthepictureshows?

CHEMICALVERSUS

ORGANICFARMINGWhere?What?Why?Organic

farmingissimplyfarmingwithoutusinganychemicals.ChemicalfarmingWhile-readingReadthetext,andanswerthequestions:1.Whatischemicalfarming?Chemicalfarmingisfarmingusingchemicalpesticidesandartificialfertilizers.2.Whatisorganicfarming?Organicfarmingissimplyfarmingwithoutusinganychemicals.

COrganicmethodsforproducingrichsoil

DTheproblemswithchemicalfarmingPara.1-2Para.3Para.4Para.5

AWhatorganicfarmingis

BWhyman-madechemicalsarestillusedinfarmingReadandmatch.Readthetext,andthenanswerthequestions.11.Whydidmanyfarmerswelcometheintroductionofchemicalfarming?2.Whatconcernsmanypeopleabouttheuseofpesticides?3.Whatisoneproblemwiththeuseofchemicalfertilisers?Manyfarmerswelcomedthemasagreatwaytofightcropdiseasesandincreaseproduction.Theirlong-termusecansometimesharmboththelandandpeople’shealth.Cropsgrownwiththemusuallygrowtoofasttoberichinnutrition.4.Howisorganicfarmingdifferentfromchemicalfarming?5.Whydoorganicfarmerschangethekindofcropgrowninafieldeveryyear?

Organicfarmingissimplyfarmingwithoutusinganychemicals.Organicfarmersfocusonkeepingtheirsoilrichandfreeofdiseasethroughnaturalmeans.Differentcropsaregrownbecausetheyputimportantmineralsbackintotheground,makingitreadyforthenextbatchofcrops.Thencompletethesentencesinthetable.2Para.MainideaDetail1—2Pesticidescankillhelpful

_____________________.Somepesticideshavebeen__________becauseofthe________________.Cropsgrownwithchemicalfertilisersusually_____________tobe

fullof_____________.bacteriaandinsectsprohibiteddamagetheycausegrowtoofastnutritionDPara.MainideaDetail3Manyorganicfarmersuse

________________________asfertiliser.4

Theyoften_____________________grownineachfield___________.Theyalsoplantcropsthatuse______________ofthesoiltohelp

keepitrich.5

Organicfarmingisnowherenearabletomeetthehigh________________________________.naturalwastefromanimalschangethekindofcropeveryyeardifferentdepthsneed/demandforfoodaroundtheworld

ACBPost-readingWhatisthegoalofusingorganicfarmingmethods?Doyouthinkitcanbereached?Whyorwhynot?Thegoalofusingorganicfarmingmethodsistogrowgoodfoodwhileavoidingdamagetotheenvironmentortopeople'shealth.Yes,Ithinkthisgoalcanbereached.Farmersworkedforcenturieswithoutusinganykindsofchemicalsandwithoutharmingtheenvironment,andthefoodtheyproducedwasjustfine.Languagepoints1.【教材原句】Thisaffectsthecropsgrownonthelandand,in

turn①,theanimalsandhumanswhodigest②them.这会影响土地里种植的作物,继而影响消化这些作物的人畜。①【词汇精讲】inturn相应地;转而;依次;轮流【词汇拓展】byturns轮流;交替地inone’sturn 轮到某人;接着taketurnstodosth 轮流做某事itisone’sturntodosth 轮到某人做某事单句语法填空(1)Nowthatwehavefinishedthedesign,itistheirturn

(construct).

(2)Thetwodaughterslookedaftertheirsickmother

turns.toconstructby②【词汇精讲】digestvt.&

vi.消化vt.领会;领悟【词汇拓展】digestionn.消化;领悟digestiveadj.

助消化的

用digest的适当形式填空(1)Nutrientsfromthe

foodcanbeabsorbedintotheblood.

(2)Largemealsoverloadthe

system.digested

digestive2.【教材原句】Infact,somepesticideslikeDDThavebeenprohibitedinmostcountriesbecauseofthedamagetheycausetopeopleandtheenvironment.事实上,由于对人类和环境有害,“滴滴涕”等农药在大多数国家已被禁用。【句式剖析】becauseof因为……,是介词短语,常用作原因状语,后面跟名词或代词作宾语。【温馨提示】because是连词,其后接句子;becauseof是复合介词短语,其后接名词、代词、动词-ing形式、what引导的从句等,它在句中一般做状语，表示引起事件发生的直接原因。e.g.Theteachergotangrybecauseofwhatwehaddoneinclass.。3.【教材原句】Asforchemicalfertilisers,cropsgrownwiththemusuallygrowtoofasttoberichinnutrition.至于化肥,用它们种植的作物通常长得太快,不能提供丰富的营养。【句法分析】句中的toofasttoberichinnutrition为too...to...结构。too...to...意为“太……而不能……”,表示否定含义。在该结构中,too为副词,修饰形容词或其他副词。to为不定式,后跟动词原形。不定式做结果状语,常用主动形式,其逻辑主语有时是句子的主语;若不是,不定式的逻辑主语通常由for引出。完成句子(1)我想提醒你们,无论何时开始学习都不迟。Iwanttoremindyouthatit’s_______________learn.never

too

late

to

4.【教材原句】Theymaylookbeautifulontheoutside,butinsidethereisusuallymorewaterthanessentialminerals,andtheyoftenhavelessflavouraswell.此类作物外表靓丽,而内里却经常是水分多于必需矿物质,并且往往口感较差。【词汇精讲】essentialadj.完全必要的;极其重要的【词汇拓展】beessentialto/for对……是必要的itisessentialthat...(should)do... 做……是必要的itisessentialtodo... 做……是必要的5.【教材原句】Asanalternative,somefarmershaveswitchedtoorganicfarming,andmanycustomershaveturnedtoorganicfoodwhentheyshopatthelocalgrocery.作为一种替代方法,有些农民已经转向有机耕作,而且许多消费者在当地食杂店购物时,也转而选择有机食品。【词汇精讲】alternativen.可供选择的事物adj.可供替代的;非传统的【词汇拓展】analternativeto...

……的替代物(to是介词)havenoalternativebuttodosth别无选择只好做某事havethealternativeofdoingsth有做某事的选择6.【教材原句】Whydifferentcropsaregrownisbecausetheyputimportantmineralsbackintotheground,makingitreadyforthenextbatchofcrops.为什么要种植不同的作物,是因为他们把重要的矿物质放回地里,让它为下一批作物做好准备。【句法分析】本句是复合句，主语是由主语从句Whydifferentcropsaregrown充当，is是系动词，表语是由表语从句becausetheyputimportantmineralsbackintotheground充当。makingitready...动词-ing形式短语做结果状语。动词-ing形式短语做结果状语,相当于一个并列谓语,所表示的是谓语动词的直接结果,是意料中的结果。【温馨提示】动词-ing形式短语做结果状语时常用逗号与主句隔开,表示与主句的动作之间有必然的因果关系,有时在其前加副词thus;动词不定式做结果状语往往表示出乎意料的结果或不好的结果,而且不定式前常加only。7.【教材原句】Therefore,thereisstillalongwaytofindasuitablesolutionthatputssufficientfoodonthedinnertablewhilekeepingpeopleandtheenvironmentashealthyaspossible.因此,想要找到一个合适的解决方案,使人类和环境尽可能保持健康,又让人们有足够的食物可吃,这还有很长的路要走。【句式剖析】本句是一个复合句。thereisstillalongway...是主句,thatputs...是定语从句,whilekeeping是省略的时间状语从句。as...aspossible尽可能……。【句式拓展】as...aspossible相当于as...asonecan,使用时需要注意can的变化。e.g.Youshouldreadmoreandmorebooksascarefullyasyoucan!Beforewriting3Writeanargumentativeessaygivingyouropiniononchemicalororganicfarming.Discussthesequestionsingroups.Istheauthorofthepassagefororagainstorganicfarming?Howdoyouknow?Whatotherdisadvantagesofchemicalfarmingdidtheauthornotlist?Howmightthefollowingitemsbeproblemsandhowimportantaretheyfororganicfarming?naturalanimalwasteusedasfertiliserhighercostofproducingfoodgreatereffortrequiredtofarmWhatotherdisadvantagesoforganicfarmingcanyouthinkof?写作指导辩论报告属于应用文文体之一，同时又具有议论文的特点，是对某个话题的辩论。该类文章一般分为三部分：第一部分：开门见山，说明自己的看法或观点；第二部分：列举支持方的观点及其理由；或列举反对方的观点及其理由；第三部分：得出结论或给出自己的观点。辩论报告[文体特征]1.文章短小精悍，语言精练，准确易懂；2.时态常用一般现在时。[常用表达]1.Wehadadiscussionabout...2.I’mwritingtotellyouaboutadiscussionwehavehadadiscussionabout...3.Opinionsaredividedonthisissue./Opinionsaremainlydividedintotwogroups.4.Differentpeople,however,havedifferentopinionsonthismatter.5.Peoplewhoareagainsttheideathinkthat...WhilewritingDecidewhetheryourgroupsupportschemicalfarmingororganicfarming.Comeupwiththreemainpointstosupportyouropinion,andthenaddatleastonedetailtosupporteachmainpoint.Completetheoutlinebelow.Topicsentence:Inmyopinion,_______farmingispreferableto____________farmingbecause____________________________Point1:_________________________________________

(Detail)____________________________________Point2:_________________________________________

(Detail)____________________________________Point3:_________________________________________

(Detail)____________________________________Conclusion:______________________________________Useyouroutlinetowriteashortessaygivingyouropiniononthetopic.Writeanargumentativeessay

明确体裁话题确定时态人称

布局文章架构

列出核心要点

开头：介绍农业发展概况和有机农业的出现。中段：展开论述，分层次介绍化学农业和有机农业的区别，有机农业的优势。结尾：总结观点，提出建议。支持有机农业文体：议论文以现在时为主、兼顾过去时、将来时；第一、三人称1.化学农业的缺点。2.有机农业的优点，人们对健康的重视和选择有机农业的理由。4Exchangeyourdraftwithapartner.

Doesthewriterdoagoodjobofexpressinghis/heropinion?Doeseachparagraphhaveonemainidea?Doeseachparagraphhaveatleastonedetailtosupportitsmainidea?Doesthewritersequencethepointsinalogicalorder?Doesthewriterdoagoodjobpersuadingyoutoaccepthis/heropinion?1.Usethechecklisttohelpyoureviewyourpartner’sdraft.

2.Takeyourdraftbackandreviseit.Sample

Writing

Inmyopinion,organicfarmingispreferabletochemicalfarmingbecauseofthebenefitstotheenvironmentandtopeople,andbecauseorganicfoodismorenutritious.

Tobeginwith,chemicalfarmingharmstheenvironment.Sincechemicalpesticidesarenotfoundinnature,normalnaturalprocessescannotgetridofthem.Instead,thechemicalstendtoaccumulateinthesoilandwater,andareabsorbedinthefoodchain,wheretheypoisonwildlifeanddomesticanimals.Thisaffectsusdirectly,becauseweendupeatingplants,dairyproducts,eggs,andmeatthathavehighlevelsofpesticides.Thinkaboutit:Thepurposeofthepesticidesistokill“pests”,thatis,tokillinsects.Somethingthatcankillaninsectprobablyisnothealthyforapersontoeat.Whileitmaybetruethatthefoodwe