高中英语《Unit4 Astronomy the science of the stars》教案（3）新人教版必修3-新人教版高一必修3英语教案VIP免费

Period3LanguagepointsinreadingTeachingGoals:1.TogetSstobetterunderstandthetext.2.TohelpSsthemastertheusagesofimportantwordsandexpression3.TogetSstoanalyzethedifficultsentencesofthetext.TeachingProcedures:StepIReadandfindoutthedifficultiesDivideSsintogroups,askthemtoreadingroupsandfindoutthedifficultexpressionsandsentences.StepIIExplanationofdifficultiesAskstudentstolistouttheirdifficultiesonblackboard.Bydiscussing,studentscansolvesomeofthem.Analyzethedifficultiesbelow:1.Whatitwastobecomewasuncertainuntilbetween4.5and3.8billionyearsagowhenthedustsettledintoasolidglobe.随后它会变成什么没人能知道，直到38-45亿年前，这团尘埃才慢慢地形成一个固体的球状物。【分析】a.此复合句的主句为Whatitwastobecomewasuncertain；从句为_____引导的定语从句。whenb.主句中包含一个由what引导的主语从句Whatitwastobecome。c.until是介词，与其前带否定前缀的形容词uncertain构成not...until句式，表示“到……才，在……之前”，引导between4.5and3.8billionyearsago作时间状语。这句话还可以这样表述：Nobodyknewwhatthecloudofdustwouldbecomebeforeitturnedintoasolidglobebetween4.5and3.8billionyearsago.2.Theearthbecamesoviolentthatitwasnotclearwhethertheshapewouldlastornot.a.此复合句的主句为Theearthbecamesoviolent；从句为_____引导的结果状语从句。thatb.so...that...如此……以致……，其中that可以省略。c.结果状语从句中包含一个由whether引导的主语从句，____是形式主语。it这句话还可以这样表述：Peopledidn’tknowwhetherthesolidglobewouldkeeptheshapeornot,becausetheearthdidn’tstopexploding.3.Theywereintimetoproducecarbon,...,whichweretomaketheearth’satmosphere.intime:soonerorlater;eventuallye.g.I’llseehimintime.intime(forsth./todosth.):notlatee.g.Shewillbebackintimetopreparedinner.与time相关的短语:innotime立刻,马上attimes有时atatime每次;依次onceuponatime从前ontime按时;准时atonetime从前forthetimebeing暂时fromtimetotime不时地atmosphere意为“大气，气氛等”。e.g.Therewasanatmosphereofviolenceandinsecurity.他们之间以前有种相互信任的气氛。4.Whatisevenmoreimportantisthatastheearthcooleddown,waterbegantoappearonitssurface.【分析】a.本句的结构是：主语从句（Whatisevenmoreimportant）+系动词（is）+表语从句（thatastheearth...onitssurface.）b.表语从句中含有一个由___引导的时间状语从句。这句话还可以这样表述：Waterbegantoappearontheearthbecauseitcooleddown,andthisismoreimportant.5.Thisproducedachainreaction,whichmadeitpossibleforlifetodevelop.【考点】it作形式宾语，真正宾语常为不定式或从句。【考例1】Wefeel_____ourdutytomakeourcountryabetterplace.AA.itB.thisC.thatD.one【考例2】Whydon’tyoubring_____tohisattentionthatyou’retooilltoworkon?BA.thatB.itC.hisD.him【点拨】都选it。都考查it作形式宾语。考例1中，it指代tomakeourcountryabetterplace；考例2中，it指代_________________________。thatyou’retooilltoworkon6.Theyproducedyounggenerallybylayingeggs.lay-laid-laid-laying放,把......放在......;产卵e.g.Helaidhisbooksonthedesk.注意:lay(laid;laid;laying)放置;产卵lie(lay;lain;lying)躺;位于lie(lied;lied;lying)说谎7.…,becausetheygavebirthtoyoungbabyanimals...【寓词于境】仔细阅读下列句子，并试着总结givebirthto的含义及用法。1)Mrs.Whitegavebirthtoafinehealthybabyinherlatethirties.2)Marygavebirthtoahealthybabygirl.3)Itwasthiseventthatgavebirthtothepeacemovement.【归纳】givebirthto后可直接跟名词，意为“_____”（句1和句2），也可意为“_____”（句3）。分娩产生【拓展】atbirth出生时since/frombirth自出生后dateofbirth出生日期8.Theyareputtingtoomuchcarbondioxideintotheatmosphere,whichpreventsheatfromescapingfromtheearthintospace.他们把太多的二氧化碳释放到大气层中,这就使得热量不能从地球上散发到太空中去。阅读下列句子,注意prevent...from的意思和用法。1)Therewasnothingtopreventherfromdoingso.2)Wemustpreventthewaterfrombeingpolluted.3)Theemperororderedhisporterstopreventthespeakerenteringthebuilding.[归纳]prevent...from的意思是___________________________。from后多跟动词-ing形式(句1、句2)；有时可省略from(句3)。制止、阻止、使……不做某事[拓展]近义短语有:stop...from阻止……干某事;keep...from阻止……干某事。注意:prevent和stop后的from都可以省略,而keep...from中的from则不能省略，如果省略了,其意义将发生改变。StepIIIExercise