人教版高中英语必修4第二单元-Using-LanguageⅡ(共36张PPT)-(1).ppt

人教课标高一必修4Unit2 Unit2Workingtheland UsingLanguage Whatdofarmersusuallyputonthesoiltomakecropsgrowfast Fertilizers Howmanykindsoffertilizersdofarmersuse Andwhatarethey Therearetwokinds Theyarechemicalfertilizersandnaturalones Chemicalfertilizers Naturalfertilizers Naturalwastefromanimalsanddeadplants Now whichonedoyouprefer A B aproductofchemicalfarming aproductoforganicfarming greenfood organicfood 1 Doyouknowwhatisorganicfarming 2 Whichkindoffertilizerdofarmersusewhentheyaredoingorganicfarming chemicalfertilizersornaturalfertilizers Pre reading ChemicalOrOrganicFarming Reading 1 Scanthepassageandgetthemainideaofit The between farmingand farming comparison chemical organic 2 Findoutandunderlinethetopicsentenceofeachparagraph Recently however scientistshavebeenfindingthatlong termuseofthechemicalfertilizerscancausedamagetothelandand evenmoredangerous topeople shealth Whataresomeoftheproblemscausedbychemicalfertilizers Findoutandunderlinethetopicsentenceofeachparagraph Para1 Para2 Skimming Para3 Para4 Withthesediscoveries somefarmersandmanycustomersarebeginningtoturntoorganicfarming Organicfarmersalsousemanyothermethodstokeepthesoilfertile Secondreading 5ms Readthetextagainandanswerthefollowingquestions 1Whyarechemicalfertilizerssopopularinfarmingtoday 2Whatproblemscanbecausedbyusingchemicalfertilizers 3Whatisorganicfarming 4Whatisthemainreasonforusingorganicfarmingmethods 1 Whyarechemicalfertilizerssopopularinfarmingtoday Theycanstopcropdiseaseandincreaseproduction 2Whatproblemscanbecausedbychemicalfertilizers Therearethreeproblems First chemicalfertilizersaffectthesoilandthewatersupplybadly Second theyallowfarmerstogrowthesamecropyearafteryearandexhaustthesoil Third theykillbothhelpfulandharmfulpests Organicfarmingissimplyfarmingwithoutusinganychemicals 3Whatisorganicfarming 4 Whatisthemainreasonforusingorganicfarmingmethods Ahealthysoilreducesdiseaseandhelpscropsgrowstrongandhealthy Thirdreading 8ms Readthetextagain andfillinthefollowingforms 1 Leavingchemicalsinthegroundforalongtimeisnotgoodforthesoilorthewatersupply 2 Farmeroftengrowthesamecropyearafter Asaresult thesoilgetsexhausted 3 Chemicalfertilizerskillbothhelpfulandharmfulbacteriaandpests Inwhatconditiondoyouthinkgreenfoodgrow dirtyairdirtywatersuppliesinindustrialareasmanychemicalfertilizers clean fresh clean awayfrom freeof Inrecentdays scientists discover thatusingchemicalfertilizersforalongtimecanbe harm tothelandandalsotopeople shealth Thereareseveralproblems cause bychemicalfertilizers Theydamagethelandandstayinthewaterforalongtime canbuildupinpeople sbodiesandleadtomany ill Therefore organicfarmingisbecoming popular withsomefarmers Theydon tuseanychemicalsandfocuson keep thesoilrich Thisalsokeepstheairandcropsfree chemicals Therearemanyothermethodstomakethelandhealthyandproductive Allofthesemethodshave samegoal togrowgoodfoodandavoid damage theenvironmentorourhealth havediscovered harmful caused which illnesses morepopular keeping from of the damaging Project Persuadefarmerstogrowthecropsbyorganicfarmingwiththeknowledgelearn