北師大版高中英語選擇性必修第一冊UNIT3 Section Ⅰ Period3課件

Period３UNIT3

CONSERVATION主題語境人與自然——人類生存、社會發(fā)展與環(huán)境的關(guān)系SectionⅠ

TOPICTALK&LESSON1TheremotecontrolallowsyoutoswitcheasilybetweenTVchannels．遙控器讓你在不同電視頻道之間輕松地轉(zhuǎn)換。課時(shí)學(xué)案語言知識講練1．switchvi．&vt．轉(zhuǎn)換，改變[知識拓展]switchoff 切斷(電源等)switchon 打開(開關(guān))；接通(電源等)switch(from...)to... (從……)轉(zhuǎn)變成……， (從……)轉(zhuǎn)換到……switchsth.withsb. 和某人交換某物switchover 轉(zhuǎn)換；轉(zhuǎn)接

[即學(xué)即練]單句語法填空①Switch___theTVbeforeyougoout．②Sheswitched___thelampbecauseitwasdark．③Weaskedthemiftheywouldswitchplaces_____us．

offonwithHeaskedtoseethemanagerforsomethingurgent．他有急事求見經(jīng)理。2．urgentadj．緊急的，急迫的[知識拓展](1)urgev．

催促；敦促；力勸；強(qiáng)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/力陳某事(2)urgencyn．

緊迫；急迫；緊急的事[即學(xué)即練]單句語法填空①Thereporturgedthatallchildren_______________(teach)toswim．②Hedenouncespeoplewhourgehim________(change)hisways．③Ineednotpressonyouthe_______(urgent)ofthematter．(should)betaughttochangeurgencyAsaresulttheseendangeredanimalsmayevendieout．結(jié)果，這些瀕危動物甚至?xí)缃^。3．dieout消失；絕跡，滅絕[知識拓展]dieaway 逐漸減弱，逐漸模糊，逐漸消失diedown 逐漸降低，逐漸平息dieoff 相繼死去dieof 死于(內(nèi)因)diefrom 死于(外因)[即學(xué)即練]單句語法填空①Astheregionisbecominghotter，thiskindofgrassisdying___．②Theirchatterandlaughterdied_____asthegrouprushedoutoftheclassroom．③Whenalltheguestshadleft，thewholehousedied_____．④Weneedtotakeactionbeforealltheendangeredanimalsdie___．

offawaydownoutTheplagueoncecouldwipeoutavillage．鼠疫曾一度可以奪走整個(gè)村莊村民的生命。4．wipeout徹底毀滅[知識拓展]wipeaway 擦去，消除wipeoff 擦掉，除掉wipeup 擦凈wipesth.from/offsth. 從……上擦去……wipe...with... 用……擦……[即學(xué)即練]單句語法填空①Whenyou'vefinishedwithit，simplywipeitclean_____adampcloth．②Hewipedthemarks___thewall．

withoffItisessentialthatyourdietisvariedandbalanced．關(guān)鍵是你的飲食要多樣化，并保持均衡。5．variedadj．各種各樣的，形形色色的[知識拓展](1)variousadj．

各種各樣的

forvariousreasons 因種種理由(2)varietyn．

變化；品種；種類；多樣化avarietyof/varietiesof 多種多樣的(3)varyv．

變化；不同varywith... 隨……而變化varyfrom...to... 從……到……變化不等[即學(xué)即練]單句語法填空①Theywerelateforthemeetingfora_______(vary)ofreasons．②Thereare______________(vary)plantsandflowersinthepark．③Theweatherhere______(vary)withseasons．varietyvarious/variedvariesIftheirhabitatisthreatenedortheycannotfindenoughfood，theirnumbersmaydecrease．如果它們的棲息地受到威脅或者它們找不到足夠的食物，它們的數(shù)量就會減少。6．decreasen．減少；減少的量vi．&vt．減少[知識拓展](1)onthedecrease 在減少中adecreasein... 在……方面減少(2)decreaseto... 減少到……decreaseby... 減少了……decreasefrom...to... 從……減少到……[即學(xué)即練]單句語法填空①Thereisadecreaseofnearly7%__thenumberofvisitorstothemuseum．②Thenumberofindependentfirmsdecreasedfrom198__96．③Becauseofhumanactivity，thenumberofsomerareanimalsis___thedecrease．intoon[名師點(diǎn)津]decrease的反義詞increase的用法：increaseto增加/增長到……increaseby增加/增長了……ontheincrease在增加中Itseemedthatthewaterwastoblame．看來水是罪魁禍?zhǔn)住?．blamevt．責(zé)怪，指責(zé)[知識拓展](1)betoblame 把……歸咎于betoblameforsth. 對某事負(fù)有責(zé)任blamesb.forsth. 因某事責(zé)備某人；把某事歸咎于某人blamesth.onsb./sth. 把某事歸咎于某人/某事(2)put/laytheblameforsth.onsb.

將某事歸咎于某人get/accept/bear/taketheblameforsth.

對某事承擔(dān)責(zé)任[即學(xué)即練]單句語法填空①Ifthathappens，thecoachwilltake___blameforit．②Youarenot________(blame)．Ican'tputtheblame___you．③Youshouldn'tblameJohn___thefailure．＝Y(jié)oushouldn'tblamethefailure___John．thetoblameonforonIhadtomakeanimportantdecisionthatwouldaffectmefortherestofmylife．我不得不做出將影響我后半生的重大決定。8．a(chǎn)ffectvt．影響[知識拓展](1)affectsb./sth.

影響某人/某物(2)effectn．

結(jié)果；效力；影響；效果；作用put/oeffect 使……生效，實(shí)行……ineffect 事實(shí)上；實(shí)際上takeeffect 生效；奏效comeintoeffect 開始實(shí)施；開始生效haveaneffecton 對……有影響[即學(xué)即練]單句語法填空/一句多譯①___effect，wefeelsuperiortothem．②Thenewlawissaidtohavecome____effectfromApril．③Greatscientificachievementswill____________________aswellassociety．＝Greatscientificachievementswill_________________________aswellassociety．重大的科學(xué)成就將對我們的生活和社會產(chǎn)生很大的影響。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脅。9．beatrisk處境危險(xiǎn)，受到威脅[知識拓展](1)atriskof 處于……的危險(xiǎn)之中atallrisks＝atanyrisk 無論冒什么風(fēng)險(xiǎn)attheriskof... 冒……的危險(xiǎn)takerisks/arisk 冒險(xiǎn)take/runtheriskofdoingsth. 冒險(xiǎn)做某事；冒著做某事的危險(xiǎn)/風(fēng)險(xiǎn)(2)riskdoingsth. 冒險(xiǎn)做某事riskone'slifetodosth. 冒著生命危險(xiǎn)做某事[即學(xué)即練]單句語法填空①Hejumpedintotheriver__theriskoflosinghislife．②Ididn'twanttotaketheriskof_______(leave)Johnalone．③Heworkedhard，forhecouldn'trisk______(lose)thegoodjob．＝Heworkedhard，forhecouldn'ttake/runtherisk___losingthegoodjob．a(chǎn)tleavinglosingof(教材p.53)ItisclearthathumanactivityhasnegativelyaffectedallotherspeciesonEarth，includinganimalsandplants．很明顯，人類活動已經(jīng)對地球上所有其他物種產(chǎn)生了負(fù)面影響，包括動物和植物。it形式主語[句式分析]句中it是形式主語，真正的主語是后面的that從句。[例1]Itiscertainthatfreemedicalcarewillbegiventomostpeopleinourcity．可以確定的是我們城市的多數(shù)人將享受免費(fèi)醫(yī)療。[例2]Itwasobviousthatthedrivercouldnotcontrolhiscar．顯然這位司機(jī)無法控制他的汽車了。[知識拓展]it作形式主語，真正的主語為that引導(dǎo)的從句的常見形式有：(1)Itbe＋形容詞(obvious，possible，strange，natural，important...)＋that從句。(2)Itbe＋名詞短語(apity，afact，awonder，ashame，anhonour，nowonder...)＋that從句。(3)Itbe＋過去分詞(said，thought，hoped，believed，declared，supposed，reported...)＋that從句。(4)It＋不及物動詞(seem，occur，happen...)＋that從句。[即學(xué)即練]完成句子①________________nobodywillliketohavedinnerinsuchadirtyplace．很明顯，沒有人想在這么臟的地方吃飯。②_________________wefailedtofulfilthetaskaheadoftime．我們沒能提前完成任務(wù)，真感到慚愧。③_______________itistheearliestandlargestpaper-makingworkshopsiteeverfoundinancientChina．人們認(rèn)為這是迄今為止在中國發(fā)現(xiàn)的最早和最大的造紙作坊。④____________________Ihadleftmyticketathome．我突然想起把票忘在家里了。ItisobviousthatIt'sashamethatItisbelievedthatItoccurredtomethatⅠ．單句語法填空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．單句寫作1．如果我們不采取行動，許多物種將很快滅絕。Manyspecies_______________ifwedon'ttakeaction．2．在這些無私的醫(yī)生的影響下，我喜歡上了這個(gè)職業(yè)。______________________________，Ihavedevelopedadeepaffectionforthecareer．willsoondieoutAffectedbythoseselflessdoctors3．正當(dāng)他絞盡腦汁尋找原因時(shí)，他突然想到他們一定要為這次事故負(fù)責(zé)。Whilehewasrackinghisbrainforreasons，itsuddenlyoccurredtohimthattheymust________________________．4．一只兇猛的狼追趕著我，我意識到我有危險(xiǎn)。IrealisedthatI__________withafiercewolfchasingme．5．建議孩子們與父母溝通，為建立和諧的家庭關(guān)系作出貢獻(xiàn)。__________________childrenshouldcommunicatewiththeirparents，makingcontributionstobuildingaharmoniousfamilyrelationship．betoblamefortheaccidentwasatriskItissuggestedthatⅢ．課文語法填空InourEarth'shistory，therehavebeenfivetimes1．_____lifeonEarthhasalmostended．Thethirdmassextinction2．______(kill)90%to96%ofallspeciesandthefiftheventcausedthe3