人教版高中英语课件：unit 13 reading.ppt

unit13 thewaterplanet stepone pre reading pre reading structureofthepassage 1minutetoskimthepassage focusingonthetitles titleandsubtitles inthetextandthenfillinthechartbelow youdonotneedtoreadthewholetext thepropertiesofwater chemicalstructure salinity density heatcapacity oceanmotion steptwo reading skimandfindoutthetopicsentences taskone topicsentenceofheatcapacity paragraph sentence topicsentenceofdensity paragraph sentence 4 thedensityofpurewateris1 000kg m3 meaningthatonecubicmetreofwaterweighsonethousandkilogrammes 5 heatcapacityisthemountofenergyittakestoraisethetemperatureofasubstancebyonedegreecentigrade topicsentenceofoceanmotion paragraph sentence 6 sincechangesinsalinityandtemperatureaffectwater sdensity thewaterintheoceanisalwaysmoving topicsentenceofthetext paragraph sentence topicsentenceofsalinity paragraph sentence topicsentenceofchemicalstructure paragraph sentence 7 3 2 learningaboutthepropertiesofwaterhelpsusunderstandlifeonourplanet thechemicalstructureofwatermakesitanexcellentmediumforlife thesalinityoftheearth soceansisaboutthirty fivepartsperthousand meaningthatthereareaboutthirty fivegrammesofdissolvedsolidsandgasesinonekilogrammeofwater scanandfindoutthemainidea tasktwo para1 para2 para3 para4 para5 para6 thepropertiesofwatermaketheoceanagreatplacetolivein thechemicalstructureofwatermakesitanexcellentmediumforlife thesalinityofseawatereffectsbothitsweightandfreezingpoint marineanimalsandplantstakeadvantageofthedensityofseawater theheatcapacityofwaterkeepsthetemperatureoftheoceansteady makingitasafeandcomfortablehabitat para6 oceanmotionaddsenergytothemarineecosystemsandmovesnutrientsaround stepthreepostreading scanandfillintheform taskthree chemicalstructure good becausewaterispolar itcanbreakdownnutrientsquickly theycanquicklybecomeavailabletootherlivingcreatures thewatermoleculeismadeupoftwohydrogenatomsandoneoxygenatom thewatermoleculeispolar ithasaslightlynegativeandaslightlypositiveend density densityistherelationshipbetweenmassandvolume good marineanimalsandplantstakeadvantageofthedensityofwater ithelpssmallcreaturestofloat becausethedensityofwaterdecreaseswhenitfreezes theoceanneverfreezestotally heatcapacity heatcapacityistheamountofenergyittakestoraisethetemperatureofasubstanceonedegreecentigrade good theheatcapacityofwaterkeepstheoceansatasteadytemperature whichmakesitagoodplacetoliveforcreaturesthataresensitivetosuddenchangesintemperature thewaterintheoceansalsokeepsthetemperatureofearthsteady oceanmotion densewatersinksandlessdensewaterispushedtothesurface sothewaterintheoceanisalwaysmoving good thecirculationaddsenergytomarineecosystemandmovesnutrientsaround taskfourtrueorfalse true t orfalse f 1 lifeontheearthbeganonthelandsomethreebillionyearsago 2 lifeintheoceanrangesfromtinyplanktontogiantwhales 3 thewatermoleculeismadeupoftwooxygenatomsandonehydrogenatoms 4 becausewaterispolar itcannotbreakdownnutrientsquickly 5 waterissolidatroomtemperature 6 seawaterissimilartopurewaterinmanyways butisheavierandhasahigherfreezingpoint 7 asubstancewithhigherdensitywillfloatonasubstancewithlowerdensity 8 becausethedensityincreaseswhenthewaterfreezes theoceanneverfreezes 9 theheatcapacitymakestheoceanasafeandcomfortablehabitattolivein languagepoints wordscompetition example otmaquienusdliooasbrbcgrnetidearupenhroygdeyoxgenassmfatol atomuniquesolidabsorbcentigradepurehydrogenoxygenmassfloat rangefrom torangebetween and 海洋里的生物从微小的浮游生物到巨大的动物 如鲨鱼和鲸鱼 都无所不包 1 theiragesrangefrom12to25 2 pricesrangebetween30yuanand50yuan 1 lifeintheoceansrangesfromthetiniestplanktonallthewayuptogiantslikeshakesandwhales 从 到 之间变化 2 thenutrientsinwhateverfallsintotheoceanquicklybecameavailabletootherlivingthings 通过任何渠道进入海洋的营养物质都能很快被其他生物所利用 whatever引导名词性从句 相当于anythingthat 1 itisnotwisetogivechildrenwhatevertheywant 宾语从句 2 whatever doisforyourgood 主语从句 3 takewhateveryouwant 宾语从句 注意 whatever引导名词性从句时 不能用nomatterwhat代替 拓展 引导状语从句时 nomatterwhat whatevernomatterwho whoevernomatterwhere wherevernomatterwhen whenevernomatterhow however 1 不管发生什么事 我们都决心完成任务 whateverhappens wearedeterminedtocompletethetask nomatterwhathappens 2 无论你什么时候来 我们都欢迎 3 无论谁触犯了法律 他最终都会受到惩罚 nomatterwhenyoucome youarewelcome wheneveryoucome nomatterwhobreakslaw hewillbepunishedintime whoeverbreakslaw 3 eventhoughthepurewateriswhatgivesseawateritsmainproperties thesalinityofseawateraffectsbothitsweightandfreezingpoint 尽管是纯水赋予了海水的主要特征 然而海水的盐度却影响了它的重量和冰点 whatgivessea thethingthatgivessea 为表语从句 她不是她以前的样子了 sheisnotwhatsheusedtobe 4 marineanimalsandplantstakeadvantageofthedensityofwater 海洋动物和植物利用了水的密度的特性 takeadvantageof1 itookadvantageofthefineweathertoplaytennis 利用 机会 2 heoftentookadvantageofhertrustfulness 利用 别人的弱点或处境 haveanadvantageover 在某方面比较有利1 yousee youhaveanadvantageoverme youcanmakeadress 5 watercanabsorbandgiveoffalotofheatwithoutbigchangesintemperature thuscreatingastableenvironment 海水可以吸收或释放出大量的热量而其温度不会变化很大 因此 能创造一个稳定的环境 absorb吸收blackclothabsorbsheat beabsorbedin 专心于iwasabsorbedinabookanddidn thearyourcall giveoff释放 theflowersgiveoffasweetfragrance stable稳定的 astablejobhischaracterisverystable 6 mostanimalsaresensitivetolargeorsuddenchangesintemperature 大多数动植物对于温度的巨变或突变都是很敏感的 besensitiveto 对 敏感1 sheisverysensitivetothecold heat 2 youshouldnotbesosensitivetocriticism sensitive敏感的 神经过敏的 神经质的asensitiveskin过敏的皮肤 fillintheblankswiththeproperwords thefirstletterhasbeengiven 1 o isagaswithoutcolor tasteorsmell 2 ana cancombinetoformamolecule 3 thed ofthefogmadeitdifficulttoseewhereweweregoing 4 h isthelightestgaswithnocolour