科普版九年级英语上册《Topic2AlltheseproblemsareveryseriousSectionC》优质课ppt课件.pptx

Unit2SavingtheEarthTopic2Alltheseproblemsareveryserious.SectionC

Discuss:1. Allofthehumanshaveahome.It’sthe.Areallthethingsthatwehavedonegoodforourplanet?Whathavehumansdonetodestroyourhome?earth

oxygen[?ks?d??n]氧气aspecialkindofoxygencalled“ozone”(O3)[??z??n]臭氧

ozonelayer臭氧层[??z??n][le??(r)]It’slikeanumbrellaoftheearthandprotectstheearth.ButWhat happenstotheozonelayer(theumbrella)?There’resomeholes.Goodorbad?

directly.Toomuchharmfulradiationfromthesunpasses throughtheholeandreachestheearth

carbondioxide(CO2[kɑ?(r)b?n][d)a??ɑ:ksa?d]二氧化碳1.Carbondioxidemainlycomesfrom.burningoil, coaland wood

2.Theheatfromthesuncan’tescape（ 出）sothetemperatureis rising.Thisiscalled“ thegreenhouseeffect .”Morecarbondioxidearoundtheearth

Newwordstakeaway 拿走oxygen [?ks?d??n] n.氧气hole [h??l] n. 洞，坑ozonelayer [??z??n][le??(r)]臭氧层radiation[.re?die??(?)n] n.放射，放射物directly[d?rek(t)li] adv.直接地carbonddioxide [kɑ?(r)b?n][da??ɑ:ksa?d]n.二氧化碳n.种类，形式form [f?:rm]v.(使）出现；（使）形成blanket [?bl??k?t] n.毛毯，毯子escape [??ske?p] v.逃脱， 出，逃跑rise [ra?z] v.上升，起床，升起Thegreenhouseeffect 温室效应refer[r??f?:(r)]to v.提到，涉及，有关

trafficpollutionfactorypollutionmorecarbondioxidetheozonelayerfewertreesCanyoumatchthem?1aReadandunderstand.

P401.ChoosesuitabletittlesforParagraphs2-6.Thenwriteitdowninfrontofeachparagraph.A.Trafficpollution B.Factorypollution C.FewertreesD.Theozonehole E.MorecarbondioxideThe earth is 4.6 billion years old. We humanshave lived on the earth for only 35 000 years, butduringthisperiod,wehavechangedourplanetalotinmanyways.Somethingswe’vedoneareverygoodfortheearthwhilesomearebad.FewerTreesAllovertheworld,peoplehavecutdownmillionsoftrees.Whenitrainsorwhenthewindblows,theearthistakenaway.Forestshavebecomedeserts,somanykindsofanimalsandplantsaredisappearing.

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