狀語從句 語法填空過關(guān)訓(xùn)練-高考英語一輪復(fù)習(xí)

備考高考英語一輪復(fù)習(xí)-狀語從句+語法填空過關(guān)訓(xùn)練狀語從句詳解引導(dǎo)時間狀語從句的連詞有when,while,as,before,after,until,assoonas,since,themoment,instantly,once等。一、when,while和as的用法1.when既可引導(dǎo)一個持續(xù)性動作，也可引導(dǎo)一個短暫性動作，可用于主句和從句動作同時發(fā)生或從句動作先于主句動作發(fā)生的情況。WhenIlivedthere,IusedtogototheseashoreonSundays.我住在那里時，星期天常到海濱去。Whenthefilmended,thepeoplewentback.電影一結(jié)束，看電影的人便回去了。特別點擊：when引導(dǎo)時間狀語從句，還可意為“正在這時”，表示某件事正在發(fā)生或剛剛發(fā)生時，突然發(fā)生另一動作。beabouttodo....when...正準(zhǔn)備做某事，這時·…bedoing...when...正在做某事，這時……beonthepointofdoing...when...正要做某事，這時··hadjustdone...when...剛做完某事，這時…··…Tomwasabouttoclosethewindowwhenhisattentionwascaughtbyabird.湯姆正準(zhǔn)備關(guān)窗戶，這時他的注意力被一只鳥吸引住了。2.while引導(dǎo)的動作必須是持續(xù)性的，側(cè)重主句動作和從句動作相對比。Pleasedon'ttalksoloudwhileothersareworking.別人工作時，請別高聲談話。3.as引導(dǎo)一個持續(xù)性動作，多用于主句和從句動作同時發(fā)生。Johnsingsasheworks.約翰一邊工作，一邊唱歌。二、assoonas,themoment,theminute,thesecond,theinstant,nosooner...than,hardly/scarcely...when...immediately,directly,instantly的用法這些從屬連詞引導(dǎo)的從句都表示從句的動作一發(fā)生，主句的動作隨即發(fā)生，常譯為“一…”就……”，從句中可用一般時態(tài)代替將來時態(tài)。Themomentshearrives,wecanstart.她一到，我們就可以開始。Nosoonerhadwearrivedatthestationthanthetrainleft.我們一到車站火車就出發(fā)了Theboyburstintotearsimmediatelyhesawhismother這個男孩一看到他的母親就哭了三、till,until和not...until的用法1.在肯定句中，主句謂語動詞必須是延續(xù)性動詞，音為“某動作一直延續(xù)到某點才停止”Youmaystayheretill/untiltherainstops.你可以在這里待到雨停。2.在否定句中，主句謂語動詞必須是非延續(xù)性動詞，從句為肯定式，意為“某動作直到某時間才開始”Hewon'tgotobedtill/untilshereturns.直到她回來他才睡。3.not...until句型中的強(qiáng)調(diào)和倒裝說法。ItwasnotuntilyoutoldmethatIhadanyideaofit.(強(qiáng)調(diào)句型)=NotuntilyoutoldmedidIhaveanyideaofit.直到你告訴我，我才知道這個消息。(notuntil置于句首，主句要倒裝）四、before和since的用法1.連詞before表示“還未····就·····;不到··…··…就······；······才······：趁……還沒…··”。Beforetheyreachedthestation,thetrainhadgone.他們（還沒）到達(dá)火車站，火車就已經(jīng)開走了Wehadn'trunamilebeforehefelttired.我們跑了還不到一英里他就累了。Pleasewriteitdownbeforeyouforgetit.趁你沒忘把它記下來。2.before的句型：Itwillbe+時間段+before從句，表示“多久之后才……”。Itwon'tbelong+before從句，表示“不久之后將……”ItwillbehalfayearbeforeIcomeback.半年后我才回來。Itwon'tbelongbeforewemeetagain.不久后我們將再見面，3.since的句型：Itis/hasbeen+時間段+since從句。若從句的謂語為非延續(xù)性動詞，表示“自從動作開始以來有多久了”；若從句的謂語為延續(xù)性動詞，表示“自從動作結(jié)束/完成……有多久了”，常譯為“自從不……有多久了”。Itisthreeyearssincethewarbrokeout.戰(zhàn)爭爆發(fā)以來，有三年了。Itisthreeyearssincehelivedhere.他已經(jīng)有三年不在這里住了。五、everytime,eachtime,nexttime,thefirsttime,anytime,allthetime的用法這些短語用來引導(dǎo)時間狀語從句，表示“每當(dāng)……；每次……；下次……”等。EverytimeImetherIalwaysforgethername.每次我見到地時，我總忘了她的名字。里來。Nexttimeyoucome,doremembertobringyoursonhere.下次你來時，一定記住把你的兒子帶到這Youarewelcometocomebackanytimeyouwantto.你想回來隨時可以回來。[練全題點]單句語法填空______theaverageageofthepopulationincreases,therearemoreandmoreoldpeopletocarefor.2.Fortherisk-seekersapartofthebrainrelatedtopleasurebecomesactive,___________fortherestofus,apartofthebrainrelatedtofearbecomesactive.3.Overtime,________thepopulationgrew,peoplebegancuttingfoodintosmallpiecessoitwouldcookmorequickly.4.JustbeforeSeptember,Millerwasstruckbyacarandlosthisrightarm.Iwenttoseehim_________hecamebackfromhospital.5._________thelittlepandacried,themotherrockeditbackandforthandgaveitlittlecomfortingpats.6.__________thedamageisdone,itwilltakemanyyearsforthefarmlandtorecover.7.Ifyoumissthischance,itmaybeyears___________yougetanotherone.8.Ibelieveyouwillhaveawonderfultimehere_________yougettoknoweveryoneelse.9.Thereisonlyonemoredaytogo___________yourfavoritemusicgroupplaylive.10.Weneedtogettotherootoftheproblem____________wecansolveit.考點清單地點狀語從句和原因狀語從句一、地點狀語從句1.地點狀語從句可用where，wherever，anywhere，everywhere等引導(dǎo)。地點狀語從句可用于主句之前或之后。Wherethereisawill,thereisaway.有志者，事竟成。Whereverthereissmoke,thereisafire.無火不生煙（即無風(fēng)不起浪)。Youarefreetogowhereveryoulike.你愿意去哪里就去哪里。2.注意區(qū)分where引導(dǎo)的定語從句與狀語從句。where引導(dǎo)的地點狀語從句直接修飾動詞，而在定語從句中where作為關(guān)系副詞要跟在表示地點的先行詞后面。You'dbettermakeamarkwhereyouhavesomequestions.(狀語從句）=You'dbettermakeamarkattheplacewhereyouhavesomequestions.(定語從句)你最好在你有問題的地方做個標(biāo)記。二、原因狀語從句1.引導(dǎo)原因狀語從句的連詞有：because，since，as,nowthat，seeingthat，consideringthat等。（1）because語氣最強(qiáng)，表示必然的因果關(guān)系。IwasabsentfromthemeetingbecauseIwasill.我缺席會議了，因為我生病了。(2)since語氣稍弱，表示對方已知曉的原因或事實，意為“既然；由于”。Sinceeverybodyishere，let'sbeginourmeeting.既然大家都到場了，我們開始開會吧。（3）as語氣最弱，往往是不明顯的原因，只是對結(jié)果的附帶說明。Asitisraining,weshallnotgotothepark.因為下雨了，所以我們不能去公園。(4)consideringthat,seeingthat,nowthat和since的意義相似，都有“鑒于某個事實”的意思，that可以省略。Considering(that)everybodyishere,let'sbeginourdiscussion.鑒于大家都到場了，我們開始討論吧。Now(that)youhavegrownup,youshouldnotrelyonyourparents.鑒于你已經(jīng)長大成人，你不應(yīng)08該依賴你父母了。2.其他表示原因的方式除了狀語從句外，一些介詞短語同樣可以表示原因，這樣的短語有：becauseof,thanksto,dueto,owingto等。Becauseoftheweather,wehadtoputoffthesportsmeeting.由于天氣原因，我們不得不推遲運動會。[練全題點]單句語法填空1.Ireallyenjoylisteningtomusic________ithelpsmerelaxandtakesmymindawayfromothercaresoftheday.2.________heoncefeltlikegivingup,henowhasthedeterminationtopushfurtherandkeepongoing.3.Halfanhourlater,Lucystillcouldn'tgetataxi_________thebushaddroppedher.4.Hefailedtheexamination________hewascareless.5.Isufferedalot_________mybusinessendedinfailure.6._________itwasraininghard,Ihadtostayathome.7.Jennywasverysadoverthelossofthecellphone,__________thiswasapossessionsheespeciallytreasured.8._________youroldcarisbeyondrepair,whynotbuyanewone?考點清單目的狀語從句和結(jié)果狀語從句一、目的狀語從句引導(dǎo)目的狀語從句的從屬連詞有：sothat,inorderthat,forfearthat,incase,lest等。inorderthat與sothat兩個連詞都意為“以便……，為了……”，引導(dǎo)的狀語從句中需用情態(tài)動詞；inorderthat比sothat正式，引導(dǎo)的狀語從句可位于主句之前或之后，而sothat引導(dǎo)的從句只能置于主句之后。Inorderthatwemightseethesunrise,westartedforthepeakearly.為了能看到日出，我們很早就出發(fā)去山頂了。I'llspeakslowlysothatyoucanunderstandme.我會說慢點兒以便你能理解我2.incase與forfearthat這些從屬連詞本身帶有否定意義，意為“以免，以防”，相當(dāng)于sothat...not...或inorderthat...not.;謂語動詞有時也用“should/might/could+動詞原形”。Theboyhidhimselfbehindthetreeincase/forfearthathisfathershouldseehim.男孩躲在樹后以免他的父親看到他。Takeyourraincoatincase/forfearthatitshouldrain.帶上雨衣，以防下雨。[練全題點1]單句語法填空1.Cathyhadquitherjobwhenhersonwasborn________orderthatshecouldstayathomeandraiseherchild.2.I'llbeoutforsometime.________caseanythingimportanthappens,callmeupimmediately.3.I'lltakesomesuncreamwithmeso________thesundoesn'tburnme.4.I'mengagedintraininghardforfear_________Ishouldlosethegame.二、結(jié)果狀語從句引導(dǎo)結(jié)果狀語從句的詞主要有so,so...that...,such...that...,sothat等1.so...that...常用句型有：so十形容詞+that...so+副詞+that...somany/few/much/little十名詞+that...；so+形容詞+a/an+可數(shù)名詞單數(shù)+that....ThetextwassoboringthatIgaveupreadingithalfwaythrough.這個劇本真枯燥，我讀到一半便放棄了。HeransofastthatIfellbehind.他跑得如此快，以至于我落在后面。Hegotsolittlemoneythathisfamilyhadtoliveonwelfaremoney.他的工資很少，他的家人不得不靠救濟(jì)金生活。Beissocleveraboythatwealllikehim.他是一個如此聰明的男孩，我們都喜歡他。2.such...that...常用句型有：such+a/an+形容詞+可數(shù)名詞單數(shù)+that..;such+形容詞+可數(shù)名詞復(fù)數(shù)that...;such+形容詞+不可數(shù)名詞+that...。Itissuchaninterestingstorythatitattractsalotofchildren.這是一個如此有趣的故事，以至于吸引了許多孩子。Theyaresuchgoodchildrenthatwealllovethem.他們都是乖孩子，我們都喜歡他們。Itissuchfineweatherthatweallwanttogotothepark.天氣如此晴朗，以至于我們都想去公園。3.sothat-sothat意為“以便；因此”。Wemovedtothecountrysothatwewereawayfromthenoisyanddullcity.我們搬到了鄉(xiāng)下，從而遠(yuǎn)離了吵鬧、單調(diào)的城市。Ishoutedloudlysothatmysoncouldhearmyvoice.我大聲喊為的是讓兒子能聽見我的聲音。語法填空解-常見語法易錯點1：oneof+the+adj最高級+n復(fù)數(shù)。2：todo不定式表目的3：表被動（by提示詞），情態(tài)動詞+V-ed4：（and,but,or并列句）：（一）：詞性---形容詞，副詞，名詞可數(shù)不可數(shù)，保持一致（二）：n詞單復(fù)數(shù)（三）：時態(tài)保持一致---最常考過去時5：?？继厥饩湫停陶Z：（一）：Startdoing/starttodosthbegindoing/begintodosth（二）:Itis/was+a/adj+(forsb)+todosth（三）：Avoiddoingstopdoingenjoyoneself6:現(xiàn)在分詞V-ing表主動，過去分詞V-ed表被動7：序數(shù)詞：one,two,three----first,second,third8:結(jié)構(gòu)：the+n.+of9:Adv常考結(jié)構(gòu)：結(jié)構(gòu)1：_______+動詞，或者動詞+______.結(jié)構(gòu)2：__________+形容詞。結(jié)構(gòu)3：_______,+一個完整的句子。副詞作狀語，修飾整個句子。10：whatever,whenever,wherever,however引導(dǎo)句子（句子不缺成分）11：Adj?？冀Y(jié)構(gòu)：Adj+n.12:人稱代詞：eg:she----考her,hers,herself13:V的否定形式：eg:appear—disagreelike----dislikeAdj的否定形式：eg:possible—impossiblebelievable---unbelievableCareful---carelessspeech---speechless14:?？紩r態(tài)：時間狀語有：recently,already,sofar,yet,lately,inthepast…,by…，for+時間段.考點----用現(xiàn)在完成時have/hasdone結(jié)構(gòu)（注意：看是不是主動或被動-havebeendone）15:常與比較級連用的詞：even,much,far,thanTodo不定式表目的，往往表示比較級【考點總結(jié)-1】（一）：單詞詞性：1.必考點---連詞，冠詞，名詞，動詞2.常考點---副詞，形容詞，代詞，介詞，數(shù)詞（二）：句型：必考定語從句，?？紶钫Z從句和名詞性從句（三）：語篇的邏輯關(guān)系：1：短文上下文的時態(tài)是否一致。2：短文上下文代詞是否一致。3：短文上下文的邏輯是否一致。4；短文上下文的單詞詞性，短語搭配，從句的邏輯關(guān)系是否正確?！究键c總結(jié)2-各個擊破】動詞：動詞時態(tài)，語態(tài)，三單，非謂語，主動被動，特殊句中的特殊用法?？迹翰榭磿r態(tài)是否一致。（二）：形容詞與副詞的誤用。（三）：名詞的單復(fù)數(shù)誤用。（四）：代詞的誤用。（五）：介詞的誤用、缺少或多余。（六）：時態(tài)的錯誤。（七）：連詞的誤用。（八）：一些固定結(jié)構(gòu)的誤用。（九）：定語從句中關(guān)系詞的誤用（十）：些常用詞的誤用。（十一）：查連詞結(jié)構(gòu)是否平行一致?？键c單詞過關(guān)-復(fù)習(xí)鞏固1:humorous.adj.有幽默感的，滑稽有趣的→humorously.adv.幽默地→humor.n幽默，滑稽2:silent.adj.安靜的，沉默的→silently.adv.安靜地→silence.n.安靜，沉默3:help.n/v幫助，有用，作用→helpful.adj.有用的，有幫組的→helpless.adj.無助的，感到絕望的4:shyness.n.害羞，靦腆→shy.adj.害羞的，靦腆的5:private.adj.私人的，隱私的→privately.adv.私人地→privacy.n.隱私6:guard.n.警衛(wèi)，看守→guard.v.守衛(wèi)，保衛(wèi)7:require.v.要求，需要→requirement.n.要求，需要8:Europe.n.歐洲→European.歐洲人/adj.歐洲的9:British.adj.英國人的→Britain.n.英國10:public.n.民眾→public.adj.公開的，公眾的→publicly.adv.公開地11:influence.n/v.影響→influential.adj.有影響的12:absent.adj.缺席的，不在的→absence.n.缺席，不在13:fail.v.不及格，失敗，未能（做到）→failure.n.失敗14:exact.adj.準(zhǔn)確的，確切的→exactly.adv.確切地，準(zhǔn)確地15:pride.n.驕傲，自豪→proud.adj.感到自豪的，驕傲的16:general.n.將軍→general.adj.總的，普遍的，常規(guī)的→generally.adv.普遍地17:introduce.v.介紹，引入→introduction.n.介紹，引進(jìn)18:educate.v.教育，教導(dǎo)→education.n.教育→educational.adj.教育的，有教育意義的→educator.n.教育家19:manage.v.完成（困難的事），成功地應(yīng)付（困難局面）→management.n.管理→manager.經(jīng)理，管理者20:society.n.社會，社交→social.adj.社交的，社會的21:support.n/v.支持→supporter.n.支持者22:enter.v.進(jìn)入，進(jìn)去→entrance.n.入口，進(jìn)入處23:choice.n.選擇，挑選→choose.v.選擇，挑選過關(guān)訓(xùn)練1-單句語法填空第一組單句語法填空Mikeinsistedthathe(be)rightandthatwe（cycle）theretoavoidtheheavytraffic.ThenumberofolderAmericanspreferring(work)ratherthanretireisontheincrease.Suchapositiveattitudelifeplaysanimportantpartinliftingyourspirits.Sheleftschoolthreeyearsagoand(work)asanurseeversince.Hefoundthatthetaskwasverydifficult(complete).Therewasnowayshecouldpersuadehimherhonestyandinnocence.Ifyoudon’tspeakgoodEnglish,you’llbeabigdisadvantagewhenyoutrytogetajib.Johnisrecognizedtobe(rely)andhardworking,soyoucanrelyhim.Thoughtheymetwithgreatdifficulty,theteammadeuptheir(mind)togoonwiththeexperiments.Igotaplacenexttothewindow,soIhadgoodviewofthesidewalk.答案：1第一個空was第二個空（should）cycle此題考查insist用法，insist堅持某種觀點時后接從句不用虛擬語氣，當(dāng)表示堅持做某事時，后接從句用虛擬語氣，從句謂語用shoulddo，should可省2.towork固定句型prefertodoratherthando“寧愿做某事而不愿做某事”3.to/towardsattitude后接to或towards4.hasbeenworking因時間狀語是eversince與現(xiàn)在完成時連用，且一直在進(jìn)行，所以用現(xiàn)在完成進(jìn)行時。5.tocomplete考查句型：主語+be+adj+todo6.of詞組persuadesbofsth是某人相信某事7.atatabigdisadvantage處在不利之處8.第一個空reliable第二個空on9.minds他們下定決心，所以mind用復(fù)數(shù)10.ahaveagoodviewof看清楚，很好地看到第二組單句語法填空Thetemplecompletely(destroy)bythefirelastnightwasbuiltalongtimeago.(bury)inhisstudy,hewasn’tawarethatalltheothershadleft.Nowagreatnumberofcollegegraduatesseekingtogetahigh-paidjob.Butthenumberofpostsavailableforthemoftennotenough.(be)Thefactory,isreportedinthelocalnewspapers,willinsistonreformingthepresentsystemwhichhassloweditsdevelopment.Thoughitwasan(extreme)difficultjourney,hewasdeterminedtofinishit.(trap)intheruins,thegirlstillworeasmile,waiting(rescue).Lilymadeuphermindtotakeataxibecausetheboxwastooheavy(carry)allthewayhome.Hearingthebadnewsthattheironlysondiedintheearthquake,thecouplebursttears.Her(shock)looksuggestedthatshedidn’tbelievewhattheboysaidwastrue.Theheadmasterwrotealettertocongratulateherhergoodperformanceandtheexciting(congratulate)encouragedhergreatly.1.destroyed過去分詞作后置定語。2.Buried過去分詞狀語beburiedin埋頭于3.are，is本題考查主謂一致，anumberof+名詞復(fù)數(shù)+謂語（復(fù)數(shù)）；thenumberof+名詞復(fù)數(shù)+謂語（單數(shù)）4.as非限制性定語從句，asisreported/expected/known/predicted正如......5.extremely修飾形容詞用副詞6.Trapped;toberescued第一個空是分詞作狀語，分詞動作不是主語thegirl發(fā)出的，所以用過去分詞；第二個空不定式作目的狀語且被動，所以用tobedone形式。7.tocarry固定詞組too...to....太......而不能......8.into固定詞組burstintotears大哭起來9.shocked修飾表情look/expression用ed形式10.on；congratulations第一個空congratulatesbonsth;第二個空exciting是形容詞，后接名詞。過關(guān)訓(xùn)練2第一篇AscientificteamfromShandongUniversityhasfoundthe①_____(early)knowntearemainsintheworld,datingbackabout2400years.②_____(track)physicalevidenceoftheoriginofChina'steaculturebacktotheearlystageoftheWarringStatesPeriod(475-221B.C.)forthreeyears,thediscoveryextendstheageofthebeverage(飲料),assuggestedbypreviousstudies,

③_____morethan300years.

Theteasamples(樣本)④_____(find)fromancienttombsinZoucheng,ShandongProvince.FromAugusttoDecember2018,theteam,ledbyprofessorWangQingfromShandongUniversity,conductedthediscoveryintheruinsof⑤_____ancientcity,whichwasbuiltintheSpringandAutumnperiod(770-476B.C.)andlatertheWarringStatesperiod.

Accordingtotheresearchers,thecarbonizedsamplesfoundinanancientbowlwerelaterproven⑥_____(high)likelytobeancienttea.Thefollowingdatashowedthattwocommon⑦_(dá)____(chemical)foundinteawereloworevenabsent.Sincetheyareeasilysoluble(可溶的)inwater,theresearchersdrawaconclusion

⑧_____thetearemainswereleftbytheancientsaftertheleawasboiled.

Thefindings⑨_____

(draw)wideattentionfromhomeandabroadsinceits⑩_____(publish)inaChinesejournal.答案：earliest;Havingtracked;by;werefound;an;highly;chemicals;that;havedrawn;publishment第二篇Synsepalumdulcificum,alsoknownasthemiraclefruit,is

①_____uniqueplantknowntoproducefruitsthat,when②_____(eat),makeallsourfoodsanddrinkstastesweet.

Forcenturies,peopleinWestAfricausedthefruitsoftheSynsepalumduicificumplantto③_____(sweet)sourfoodsanddrinks.In1968,themiraculin(非洲奇果蛋白)that④_____(make)thefruitsspecialwasextractedandturnedintotablets.Thatmadeitpossiblefornearlyanyoneintheworldtoexperiencethe"tastetripping"thatthemiracle⑤_____(berry)aresofamousfor.

Itsoundslikeaningredientyou'llexpecttofindinamagicschool.Infact,themiraclefruitexistsintherealworld,notinsomefantasyuniverse,

⑥_____itseffectcanbeexplainedbyscience.Whenthefleshofthefruitiseaten,themiraculin⑦_(dá)____(basic)changesyoursenses.

Becausethemiraculincanmakesourfoodstastesweet,itcouldreducesugar⑧_____(consume),andinsomecountriesitisreallypopular.However,itmustbeconsumedeitherinfruitsor

⑨_____tablets,becausetheprotein⑩_____(destroy)whenitiscooked.

Themiraclefruit'seffectissostrongthatitmakessomepeopleenthusiasticallytryasmanysourthingsaspossiblebeforethemiraculin'seffectwearsoff.答案：a;eaten;sweeten;makes;berries;and;basically;consumption;as;willbedestroyed第三篇BeijingOpera,①_________(know)asChina'snationalopera,alsocalledPekingOpera,whichoriginatedinthelate18thcentury,isacombinationofmusic,dance,artandacrobatics(雜技).ItisthemostinfluentialandrepresentativeofalloperasinChina.ItiscalledBeijingOperabecauseitisformedinBeijing.BeijingOperahas

②_________historyof200yearsanditsorigincandatebacktooldlocaloperas,especiallyAnhuiOpera,

③_________wasverypopularinnorthernChinainthe18thcentury.In1790,thefirstAnhuiOperaperformance④_________(hold)inBeijingtocelebratetheEmperor'sbirthday.

Later,someotherAnhuiOperatroupes(班子)⑤_________(continue)performinginBeijing.AnhuiOperawaseasy⑥_________(move)andgoodatabsorbingtheactingstylesofothertypesofoperas.Beijingaccumulatedmanylocaloperas,⑦_(dá)________(make)AnhuiOperaimprovequickly.

⑧_________theendofthe19thcenturyandthebeginningofthe20thcentury,afterthemarriagefor10years,BeijingOperafinallyformed,andbecamethe⑨_________(big)ofalloperasinChina.Wecan⑩_________(honest)saythatBeijingOperaisthemostimportantoperainChina.答案：known;a;which;washeld;continued;tomove;making;At;biggest;honestly第四篇Astheworld'stopclimatescientistsreleased

①__________reportfullofwarningsthisweek,theyinsistedthatwestillhaveachance②__________(avoid)theworsteffectsofclimatechange.

The③__________(hope)approachtoaddressingtheproblemisthegiantcomputersimulationsoftheworldeconomy.They④__________(call)integratedassessmentmodels.Eachmodelstartswithdataaboutcurrentsourcesofgreenhouseemissionssuchascars,buses,auto-rickshaws(機(jī)動三輪車)andairplanes.Thenthescientistsforce⑤__________(they)virtualworldstochangethecourse,byintroducinglimitsongreenhouseemissions.Themodelsthentrytosatisfythatrequirementsinthemostcost-effectiveway,aslongasit'stechnologicallyfeasible(可行的)anddoesn'trunupagainstlimitslikethesupplyoflandorothernaturalre