北师大版高中英语选择性必修第一册UNIT3 Section Ⅰ Period3课件

Period３UNIT3

CONSERVATION主题语境人与自然——人类生存、社会发展与环境的关系SectionⅠ

TOPICTALK&LESSON1TheremotecontrolallowsyoutoswitcheasilybetweenTVchannels．遥控器让你在不同电视频道之间轻松地转换。课时学案语言知识讲练1．switchvi．&vt．转换，改变[知识拓展]switchoff 切断(电源等)switchon 打开(开关)；接通(电源等)switch(from...)to... (从……)转变成……， (从……)转换到……switchsth.withsb. 和某人交换某物switchover 转换；转接

[即学即练]单句语法填空①Switch___theTVbeforeyougoout．②Sheswitched___thelampbecauseitwasdark．③Weaskedthemiftheywouldswitchplaces_____us．

offonwithHeaskedtoseethemanagerforsomethingurgent．他有急事求见经理。2．urgentadj．紧急的，急迫的[知识拓展](1)urgev．

催促；敦促；力劝；强烈要求urgesb.todosth./intodoingsth. 敦促某人做某事urgethatsb.(should)dosth. 敦促某人做某事urgesth.onsb. 向某人提出/力陈某事(2)urgencyn．

紧迫；急迫；紧急的事[即学即练]单句语法填空①Thereporturgedthatallchildren_______________(teach)toswim．②Hedenouncespeoplewhourgehim________(change)hisways．③Ineednotpressonyouthe_______(urgent)ofthematter．(should)betaughttochangeurgencyAsaresulttheseendangeredanimalsmayevendieout．结果，这些濒危动物甚至会灭绝。3．dieout消失；绝迹，灭绝[知识拓展]dieaway 逐渐减弱，逐渐模糊，逐渐消失diedown 逐渐降低，逐渐平息dieoff 相继死去dieof 死于(内因)diefrom 死于(外因)[即学即练]单句语法填空①Astheregionisbecominghotter，thiskindofgrassisdying___．②Theirchatterandlaughterdied_____asthegrouprushedoutoftheclassroom．③Whenalltheguestshadleft，thewholehousedied_____．④Weneedtotakeactionbeforealltheendangeredanimalsdie___．

offawaydownoutTheplagueoncecouldwipeoutavillage．鼠疫曾一度可以夺走整个村庄村民的生命。4．wipeout彻底毁灭[知识拓展]wipeaway 擦去，消除wipeoff 擦掉，除掉wipeup 擦净wipesth.from/offsth. 从……上擦去……wipe...with... 用……擦……[即学即练]单句语法填空①Whenyou'vefinishedwithit，simplywipeitclean_____adampcloth．②Hewipedthemarks___thewall．

withoffItisessentialthatyourdietisvariedandbalanced．关键是你的饮食要多样化，并保持均衡。5．variedadj．各种各样的，形形色色的[知识拓展](1)variousadj．

各种各样的

forvariousreasons 因种种理由(2)varietyn．

变化；品种；种类；多样化avarietyof/varietiesof 多种多样的(3)varyv．

变化；不同varywith... 随……而变化varyfrom...to... 从……到……变化不等[即学即练]单句语法填空①Theywerelateforthemeetingfora_______(vary)ofreasons．②Thereare______________(vary)plantsandflowersinthepark．③Theweatherhere______(vary)withseasons．varietyvarious/variedvariesIftheirhabitatisthreatenedortheycannotfindenoughfood，theirnumbersmaydecrease．如果它们的栖息地受到威胁或者它们找不到足够的食物，它们的数量就会减少。6．decreasen．减少；减少的量vi．&vt．减少[知识拓展](1)onthedecrease 在减少中adecreasein... 在……方面减少(2)decreaseto... 减少到……decreaseby... 减少了……decreasefrom...to... 从……减少到……[即学即练]单句语法填空①Thereisadecreaseofnearly7%__thenumberofvisitorstothemuseum．②Thenumberofindependentfirmsdecreasedfrom198__96．③Becauseofhumanactivity，thenumberofsomerareanimalsis___thedecrease．intoon[名师点津]decrease的反义词increase的用法：increaseto增加/增长到……increaseby增加/增长了……ontheincrease在增加中Itseemedthatthewaterwastoblame．看来水是罪魁祸首。7．blamevt．责怪，指责[知识拓展](1)betoblame 把……归咎于betoblameforsth. 对某事负有责任blamesb.forsth. 因某事责备某人；把某事归咎于某人blamesth.onsb./sth. 把某事归咎于某人/某事(2)put/laytheblameforsth.onsb.

将某事归咎于某人get/accept/bear/taketheblameforsth.

对某事承担责任[即学即练]单句语法填空①Ifthathappens，thecoachwilltake___blameforit．②Youarenot________(blame)．Ican'tputtheblame___you．③Youshouldn'tblameJohn___thefailure．＝Youshouldn'tblamethefailure___John．thetoblameonforonIhadtomakeanimportantdecisionthatwouldaffectmefortherestofmylife．我不得不做出将影响我后半生的重大决定。8．affectvt．影响[知识拓展](1)affectsb./sth.

影响某人/某物(2)effectn．

结果；效力；影响；效果；作用put/oeffect 使……生效，实行……ineffect 事实上；实际上takeeffect 生效；奏效comeintoeffect 开始实施；开始生效haveaneffecton 对……有影响[即学即练]单句语法填空/一句多译①___effect，wefeelsuperiortothem．②Thenewlawissaidtohavecome____effectfromApril．③Greatscientificachievementswill____________________aswellassociety．＝Greatscientificachievementswill_________________________aswellassociety．重大的科学成就将对我们的生活和社会产生很大的影响。InintogreatlyaffectourlifehaveagreateffectonourlifeAswithalldiseases，certaingroupswillbemoreatriskthanothers．所有的疾病都是如此，一些人比另一些人更容易受到威胁。9．beatrisk处境危险，受到威胁[知识拓展](1)atriskof 处于……的危险之中atallrisks＝atanyrisk 无论冒什么风险attheriskof... 冒……的危险takerisks/arisk 冒险take/runtheriskofdoingsth. 冒险做某事；冒着做某事的危险/风险(2)riskdoingsth. 冒险做某事riskone'slifetodosth. 冒着生命危险做某事[即学即练]单句语法填空①Hejumpedintotheriver__theriskoflosinghislife．②Ididn'twanttotaketheriskof_______(leave)Johnalone．③Heworkedhard，forhecouldn'trisk______(lose)thegoodjob．＝Heworkedhard，forhecouldn'ttake/runtherisk___losingthegoodjob．atleavinglosingof(教材p.53)ItisclearthathumanactivityhasnegativelyaffectedallotherspeciesonEarth，includinganimalsandplants．很明显，人类活动已经对地球上所有其他物种产生了负面影响，包括动物和植物。it形式主语[句式分析]句中it是形式主语，真正的主语是后面的that从句。[例1]Itiscertainthatfreemedicalcarewillbegiventomostpeopleinourcity．可以确定的是我们城市的多数人将享受免费医疗。[例2]Itwasobviousthatthedrivercouldnotcontrolhiscar．显然这位司机无法控制他的汽车了。[知识拓展]it作形式主语，真正的主语为that引导的从句的常见形式有：(1)Itbe＋形容词(obvious，possible，strange，natural，important...)＋that从句。(2)Itbe＋名词短语(apity，afact，awonder，ashame，anhonour，nowonder...)＋that从句。(3)Itbe＋过去分词(said，thought，hoped，believed，declared，supposed，reported...)＋that从句。(4)It＋不及物动词(seem，occur，happen...)＋that从句。[即学即练]完成句子①________________nobodywillliketohavedinnerinsuchadirtyplace．很明显，没有人想在这么脏的地方吃饭。②_________________wefailedtofulfilthetaskaheadoftime．我们没能提前完成任务，真感到惭愧。③_______________itistheearliestandlargestpaper-makingworkshopsiteeverfoundinancientChina．人们认为这是迄今为止在中国发现的最早和最大的造纸作坊。④____________________Ihadleftmyticketathome．我突然想起把票忘在家里了。ItisobviousthatIt'sashamethatItisbelievedthatItoccurredtomethatⅠ．单句语法填空1．Itwassurprising____shepassedthedifficultexam．2．Attheriskof____________(blame)，hedrovehisfather'scartoschool．3．Oilspillsarehavingadevastatingeffect__coralreefsintheocean．4．Thenumberofteachingstaffmembersinthisschoolhasdecreased___700persons．thatbeingblamedonto5．Tom'slifewas______________(vary)andpleasantenough，onthewhole．6．Thetsunamithatfollowedengulfedthenortheastandwiped___entiretowns．7．Manyofouroldcustomsare_____(die)outdaybyday．8．Weneedtoswitch___thecellphoneandleavethechildrentoplaybythemselves．varied/variousoutdyingoff9．Thecountryneedsnewleadershipifsheistoplayarole__futuredevelopment．10．Thesocietywassetuptopreserve__________(endanger)speciesfromextinction．inendangeredⅡ．单句写作1．如果我们不采取行动，许多物种将很快灭绝。Manyspecies_______________ifwedon'ttakeaction．2．在这些无私的医生的影响下，我喜欢上了这个职业。______________________________，Ihavedevelopedadeepaffectionforthecareer．willsoondieoutAffectedbythoseselflessdoctors3．正当他绞尽脑汁寻找原因时，他突然想到他们一定要为这次事故负责。Whilehewasrackinghisbrainforreasons，itsuddenlyoccurredtohimthattheymust________________________．4．一只凶猛的狼追赶着我，我意识到我有危险。IrealisedthatI__________withafiercewolfchasingme．5．建议孩子们与父母沟通，为建立和谐的家庭关系作出贡献。__________________childrenshouldcommunicatewiththeirparents，makingcontributionstobuildingaharmoniousfamilyrelationship．betoblamefortheaccidentwasatriskItissuggestedthatⅢ．课文语法填空InourEarth'shistory，therehavebeenfivetimes1．_____lifeonEarthhasalmostended．Thethirdmassextinction2．______(kill)90%to96%ofallspeciesandthefiftheventcausedthe3