2025年外研版三年级起点必修3英语上册阶段测试试卷

…………○…………内…………○…………装…………○…………内…………○…………装…………○…………订…………○…………线…………○…………※※请※※不※※要※※在※※装※※订※※线※※内※※答※※题※※…………○…………外…………○…………装…………○…………订…………○…………线…………○…………第=page22页，总=sectionpages22页第=page11页，总=sectionpages11页2025年外研版三年级起点必修3英语上册阶段测试试卷563考试试卷考试范围：全部知识点；考试时间：120分钟学校：______姓名：______班级：______考号：______总分栏题号一二三四五六总分得分评卷人得分一、选择题(共9题，共18分)1、Fifty-threeyearsafteritwaswrittenin1958,thelovelettertoaUScollegestudentfromhisgirlfriendwho______hiswifeisfinallyonitswaytohim.A.wastobecomeB.becomesC.istobecomeD.became2、___________intheburningbuildingforhalfanhour,thelittleboywasfinallysavedbythelocalpolice.A.HavingtrappedB.TrappedC.BeingtrappedD.Trapping3、Wewillgatherforthecommunityserviceattheschoolgateat8tomorrowmorningunless________.A.otherwiseinformingB.otherwisebeinginformedC.otherwiseinformedD.havingotherwiseinformed4、Tomsoundsverymuch______inthejob,butI’mnotsurewhetherhecanmanageit.A.interestedB.interestingC.interestedlyD.interestingly5、Itwasannouncedthatonlyafterthecandidates’paperswerecollected_____toleavetheroom.A.hadtheybeenpermittedB.wouldtheybepermittedC.thattheywouldbepermittedD.thattheyhadbeenpermitted6、_______fromspace,theearthisblue.A.SeenB.SeeingC.SawD.Beingseen7、________thebestinasciencecompetition,thethreestudentswereawardedscholarshipstotaling21,000.A.TobejudgedB.JudgedC.HavingjudgedD.Judging8、________withsomefoodanddrinks,thechildrensetsailearlyinthemorning.A.EquipB.ToequipC.EquippingD.Equipped9、Theyoungman,________stealingabike,stoodthere,shakingallover.A.accusingofB.accusedofC.accusingwithD.accusedwith评卷人得分二、其他(共8题，共16分)10、Livewithroommates?Havefriendsandfamilyaroundyou?Chancesarethatifyou’relookingtoliveamoresustainablelifestyle,noteveryonearoundyouwillbereadyto____.IexperiencedthiswhenIstartedswitchingtoazerowastelifestylefiveyearsago,asIwaslivingwithmyparents,andIcontinuetoexperiencethiswithmyhusband,asheisnotcompletelyzerowastelikeme.I’velearnedafewthingsalongthewaythough,whichIhopeyou’llfindencouragingifyou’redoingyourbesttofigureouthowyoucanmakethechangeinanot-always-supportivehousehold.Zerowastewasaradicallifestylemovementafewyearsback.IremembershowingmyparentsavideoofBeaJohnson,sharinghowcoolIthoughtitwouldbetobuygrocerieswithjars,andhavesolittletrash!Afewdayslater,Icamebackwithmyfirstjarsofzerowastegroceries,andmydadcommentedonhowsillyitwasformetocarryjarseverywhere.Itcameoffasabitdiscouraging.Yetasthemonthsofreducingwastecontinued,IdidwhatIcouldthatwaswithinmyownreach.Ihadmyownbedroom,soIworkedonremovingthingsIdidn’tneed.SinceIhadmyowntoiletries(洗漱用品),Iwasabletostartpersonalisingmyroutinetobemoresustainable.Ialsoofferedtocookeverysooften,soIportionedoutabitofthecupboardformyownzerowastegroceries.Perhapsyourhouseholdwon’tentirelymaketheswitch,butyoumayhavesomecontroloveryourownpersonalspacestomakethechangesyoudesire.Asyoumakeyourlifestylechanges,youmayfindyourselfwantingtospeakupforyourselfifotherscommentonwhatyou’redoing,whichcanturnitselfintoawholehouseholddebate.Ifyouhaveindividualswhoarenotonboard,yourwordsprobablywon’tdomuchandcanoftenleaveyoufeelingmorediscouraged.Sohereismyadvice:Leadbyaction.

Whatisthetextmainlyabout?。A．Howtogetonwellwithotherfamilymembers.B．Howtohaveone’sownpersonalspaceathome.C．Howtoliveazero-wastelifestyleinahousehold.D．Howtocontrolthebudgetwhenbuyinggroceries.11、KingCanutecouldn’tstoptheocean’stidefromrollingin—canAfricaholdbackthedesert?That’scertainlywhatthecontinentistyingtodowithitsproposed“GreatGreenWall”,800km(almost5,00miles)worthoftreesthatofficialshopewillstoptheadvancementoftheSaharaDesert,whichhasbeenrapidlyexpandingsouthward.Theideawasintroducedinthe1970swhentheonce-richregionturnedbarren(贫瘠的)duetoclimatechangeandintensivelanduse.Butit’snotanewidea;ChinahasitsowndesertvegetationprojecttoholdbacktheGobiDesert!ThankstotheChineseplan,theAfricanprojectaimstoplant100millionhectaresoftreesby2030acrosstheentireAfrica.Theinitiativeisadecadein,andaround15%completed,andtherehavealreadybeenbenefitsformanycommunitiesandwildlife.It’sbringinglifebacktothecontinent’sdegradedlandscapesatanunprecedentedscale,providingnotonlyfoodsecurityandjobsbutareasontostayforthemillionswholivealongitspath.ThecreatorsofthewallhopeitwillbringanurgentlyneededsolutiontothethreatsfacingtheAfricancontinent,creating10millionjobsinruralareas,aswellaspreventing250milliontonsofcarbon.TheinitiativeisAfrica-driven,whichforthoseonthecontinent,isvital,andmayholdthekeytosuccess.“TheGreatGreenWallisaboutownership,andthathasbeenthefailureofdevelopmentaidbecausepeoplewereneveridentifiedwithit,”saidElvisPaulTangam,AfricanUnionCommissionerfortheSaharaandSahelGreatGreenWallInitiative.“Butthistimetheyidentify.Thisistheverythingof____!”Thewallmayseemlikeamoonshot,butallthebestideasusuallyare.AsThomasSankara,formerpresidentofBurkinaFasosaidin1985,“Youcannotcarryoutfundamentalchangewithoutacertaindegreeofmadness.Thecouragetoturnyourbackontheoldformulas,thecouragetoinventthefuture.”

Whatdoes“us”underlinedinParagraph3referto?。A．AfricanUnions.B．Alladvocates.C．Landowners.D．AllAfricans.12、ForoneweekinMay,morethan100,000peopleintheUKcarefullycountedtheirplasticwasteathomeinanationalinvestigationintoplasticuseandrecycling.ItwascalledtheBigPlasticCount,runbyorganizationsGreenpeaceandEverydayPlastic.Sohowdidtheygeton,andwhatdidtheydiscoverabouttheirdependencyonamaterialthathasbecomeapartofoureverydaylives?Jules,41,andherfamilythrewaway124piecesofplasticduringtheirweekofcounting.Thepackaginginpartybagsandstickerpacksforherdaughter’ssixthbirthdaywasthemostupsetting,shesays.Shehadthoughtherhouseholdwasquitelowplasticandsowas“shocked”byhowmuchtheyused.“It’sthehiddenstuffthatisn’trecyclable—likepizzawrappers—thatgetsyou,”Julesexplains.“Everysinglesheetforthestickersinthepartybagscameindividuallywrappedinitsownunrecyclablebag,andthentheywerepackedtogetherinabiggerbag,”shesays.HerchildrenarepassionateaboutprotectingtheenvironmentbutJulessaysshefindsitveryhardasaconsumertomaketherightchoices.“Wecanonlydosomuch.It’sinthemanufacturer’shands.Thewholethingissuchajuggle(杂耍).”Taylor,a25-year-oldscheduler,saysofthe70piecesofplastichecounted,itwasthecucumberpackagingthatupsethimthemost.Hehasfamilywholiveabroadwherehesaysit’seasytobuyfruitsandvegetableswithoutanyplastic.He’dalsoliketoseemorelocalproduceinshopsdirectfromfarmers,whichwouldreducetheneedforexcessivepackagingusedtotransportgoodslongdistances.“Igetprogressivelymoreupsetwiththefactthatsupermarketssellsomuchplastic,”hesays.Evenifhecouldfindplastic-freealternatives,hesaysthecostis____.“Thepriceofeverythingisgoingup,butthingsthatarebetterfortheenvironmentaremuchmoreexpensive,”hesays.

Whatdoestheunderlinedword“exorbitant”inthelastparagraphmean?。A．FlexibleB．Reasonable.C．LowD．Sky-high.13、Theyogurtthat’spastitssell-bydate.Thebananainyourlunchthatturnedbrown.Theleftoversinthefridgethatyouforgottoeat.Formostpeople,allthatfoodgoesrightintothegarbagecan.Eighttotenpercentofglobalgreenhousegasemissions(放)arerelatedtofoodwaste,accordingtoareportbytheU.N.’sIntergovernmentalPanelonClimateChange.“Whenyouthrowawayaneggorasandwich,”saysYvetteCabrera,foodwastevicedirectorattheNaturalResourcesDefenseCouncil(N.R.D.C.),“you’realsothrowingawayalltheresourcesthatwentintoproducingthosethings.”____includesnotonlyallthewater,land,andfertilizer(化肥)thatwentintoproducingthatfood,butalsothemassiveamountsoffossilfuelsusedtopowerthefarms,transportthefood,andcreatethepackaging.Thenthere’stheissueofwhathappenstofoodafterit’sthrownout.MorefoodendsupinU.S.landfillsthananyothertypeoftrash.Foodrottinginlandfillsproducesmethane(甲烷),agreenhousegasthat’sroughly25timesmorepowerfulattrappingheatintheatmospherethancarbondioxide,whichisproducedbyburningfossilfuels.

WhatdoestheauthorintendtodoinParagraph4?。A．Provideapersuasiveexample.B．Addmorebackgroundinformation.C．Discussamoreseriousconsequence.D．Summarizethepreviousparagraphs.14、KingCanutecouldn’tstoptheocean’stidefromrollingin—canAfricaholdbackthedesert?That’scertainlywhatthecontinentistyingtodowithitsproposed“GreatGreenWall”,800km(almost5,00miles)worthoftreesthatofficialshopewillstoptheadvancementoftheSaharaDesert,whichhasbeenrapidlyexpandingsouthward.Theideawasintroducedinthe1970swhentheonce-richregionturnedbarren(贫瘠的)duetoclimatechangeandintensivelanduse.Butit’snotanewidea;ChinahasitsowndesertvegetationprojecttoholdbacktheGobiDesert!ThankstotheChineseplan,theAfricanprojectaimstoplant100millionhectaresoftreesby2030acrosstheentireAfrica.Theinitiativeisadecadein,andaround15%completed,andtherehavealreadybeenbenefitsformanycommunitiesandwildlife.It’sbringinglifebacktothecontinent’sdegradedlandscapesatanunprecedentedscale,providingnotonlyfoodsecurityandjobsbutareasontostayforthemillionswholivealongitspath.ThecreatorsofthewallhopeitwillbringanurgentlyneededsolutiontothethreatsfacingtheAfricancontinent,creating10millionjobsinruralareas,aswellaspreventing250milliontonsofcarbon.TheinitiativeisAfrica-driven,whichforthoseonthecontinent,isvital,andmayholdthekeytosuccess.“TheGreatGreenWallisaboutownership,andthathasbeenthefailureofdevelopmentaidbecausepeoplewereneveridentifiedwithit,”saidElvisPaulTangam,AfricanUnionCommissionerfortheSaharaandSahelGreatGreenWallInitiative.“Butthistimetheyidentify.Thisistheverythingof____!”Thewallmayseemlikeamoonshot,butallthebestideasusuallyare.AsThomasSankara,formerpresidentofBurkinaFasosaidin1985,“Youcannotcarryoutfundamentalchangewithoutacertaindegreeofmadness.Thecouragetoturnyourbackontheoldformulas,thecouragetoinventthefuture.”【小题1】WhatdoesAfrica’s“GreatGreenWall”aimfor?。A．Offeringmorejobsforlocals.B．Stoppingtheexpansionofdesert.C．Creatingaharmonioussociety.D．ImprovingAfricanlandscapes.【小题2】WheredidAfricagettheinspiration?。A．Fromtheirpracticesofplantingtrees.B．Fromtheprocessofstoppingflooding.C．FromChina’ssuccessindesertcontrol.D．FromAfricans’wisdomandhardwork.15、Besides,10%ofrichcountriesgreenhousegasemissionscomefromfoodthatwasgrownandnevereaten.Foodwastenotonlycontributestoclimatechange,butalsofoodinsecurityandextremepoverty.Asstatedabove,inthegreatestfoodwastingcountries,therearelawsthat____producefrombeingdonatedtopeopleinneed.

Whatdoestheunderlinedword“confine”inparagraph3probablymean?。A．Refuse.B．Restrict.C．Contact.D．Protect.评卷人得分三、读后续写(共4题，共8分)16、阅读下面材料，根据其内容和所给段落开头语续写两段，使之构成一篇完整的短文。Twomonthsago,RyderKillam,a15-year-oldFrenchboywasregisteredinanewschoolinHawaii.Hejustmovedtherewithhisparents.Althoughhemissedhisoldfriendsverymuch,hemanagedtoadapttohisnewschoollifeandsoonmadealotoffriends.However,waitingfortheschoolbuseverymorningoftenmeantarealsufferingbecauseRyderwasbornwithspinabifida（脊柱裂）andhehastoliveinawheelchair.Hawaiiisoneoftherainiestplacesintheworld.Thisisnotanissueforotherstudents,butforhimthiswasadifferentstory.Heoftengotwetalloverbeforetheschoolbusarrivedduringtherainydays.Inthatcase,hecouldonlyhaveclasseswithwetclothesonorcalledhisparentstosenddryclothestoschoolandfindingaplacetogetchangedwasalsoabigchallengeforthisdisabledboy.TokeepRyderprotectedfromthebadweatherwhilewaitingforthebuseverymorning,thestudentsinRyder'sschooldecidedtotakeaction.TheyfirstuploadedapostonFacebookaskingforanunusedbusshelterbutgotnoreply.Notbeingabletofindone,thestudentsfromtheconstructionclassdecidedtotakeonthechallengeofbuildingacustomizedbusshelterforhimandquicklyputtheirhandstowork.Aspartofthehighschool'sCareerandTechnicalEducationprogram,theconstructionclassteachesitsstudentsbasicbuildingskills.Itsmaingoalistoprovidestudentswithtoolsandskillsthatwillhaverealapplicationsinfuturejobsandameaningfulimpactontheircommunity.Theyhadalreadyperformedseveralbuildingprojectsforthecommunity.Twoyearsago,theymanagedtobuilddozensofsheltersforstraycatsinthelocalpark.Soonenough,theycameupwithanideaofbuildingatwo-windowshelterforRyder.

注意：

1.续写词数应为150左右；

2.请按如下格式在答题卡的相应位置作答。However,theseteenagersfoundbuildingthisbusshelterwasnoeasyjob.

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________Thedayfinallycamewhenthenewbusshelterwasputtouse.

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________17、阅读下面材料，根据其内容和所给段落开头语续写两段，使之构成一篇完整的短文。Rishalovedschool.However,therewasoneclassRishaworriedaboutmorethananyother—art.Shedidn’tknowwhyshejustwasn’tanygoodatdrawing,painting,orcutting.Ms.Clay,theartteacher,stoodatthefrontoftheroom.“Class,nextFridayourschoolisgoingtohaveanartcompetition.”sheannounced.Ms.Claywasagreatteacher,andRishalikedheralot.ButthisannouncementmadeRishanervous.“Everyoneintheschoolwillcreateapieceofartworktoshowinthelibrary.Youcanusethedifferenttypesofartworkwehavebeenstudying.”Ms.ClaywasquiteexcitedwhenshespokewhileRishafoundherselfsinkinglowerinherchair.Rishahadthewholeweekendtoworkonherproject,butshecouldnotthinkofanythingtodo.OnMonday,Rishafeltfrightened,soafterschoolRishaaskedMs.Clayifshecouldwriteanartpaperinsteadofdoinganartproject.“Iunderstandthisprojectscaredyou,Risha,”Ms.Claysaid.“Justremember,youcancreateanykindofartyouwant.”Ms.Claysmiledather.“Artisaperson’swayofexpressinghisorherfeelings—itisn’talwayspainting,drawing,orcutting.Iknowyouwillthinkofsomethingverycreative,andIcan’twaittoseeit.”WhenRishaarrivedhome,shetookoutapieceofpaperandapencil.SherememberedMs.Clay’swords.“Artisaperson’swayofexpressinghisorherfeelings.”Rishawrotetheword“terrified”onherpaper.Shecrumpled(弄皱)thepaperandthrewittothesideofherdesk.

注意：

1.续写词数应为150左右；

2.请按如下格式在答题卡的相应位置作答。

ThenRishastaredatthecrumpledball.

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OnFriday,Rishacarefullycarriedherprojectintothelibrary.

________________________________________________________________________________________________________________________________________________________________________________________18、阅读下面材料，根据其内容和所给段落开头语续写两段，使之构成一篇完整的短文。DaysofJanuarywerepassingandeverygirlofthegirls’schoolwasveryhappyastheselectionsforplaysanddancesfortheannualfunctionwerestarted.Sneha’sclassteacher,Pravina,askedSneha,herfavoritestudent,toplaytheleadingcharacterinaplay.Becauseshewasneverallowedtoplayamalecharacter,Snehajumpedwithjoy,butsuddenlyshebecamesoseriousaboutthecostumes(戏服).“HowmanytimesIhavetotellyounottoparticipateinplaysanddances!Can’tyouunderstandthatwecan’tbuyorborrowthecostlycostume?Youcantakepartindebates,quizes,oressaycompetitionsinwhichyoudon’thavetospendmoneyandyoucanenrichyourknowledge,”hermothersaidangrilywhenSnehatoldheraboutit.Thereasonbehindallthiswastheirfinancialcondition.SnehaalwayshadanideaaboutitinherhomeandshewasmatureenoughtosayNOtoanymoneydemandingcondition.Thistime,however,thedesireoffameandtheexcitementoftheactivitywereovercomingherfear.Snehawentinherroomhidinghersadnessdeepinherheart.ShewassonervousaboutwhatwasgoingtohappenwhenshewouldtellPravinaaboutleavingtheplay.Wouldshewarnhernottoallowherinanycompetition?Nowitwasclearthatshehadtoleavetheplay.Thenextday,downheartedSnehaactedlikenothinghadhappenedandgotreadyforschool.HermomorderedhertosayNOfortheplay.SnehaalwayslovedPravinabecausewhenevertherewasaplayordance,thegirlsdidnotneedtobeworriedaboutanythingrelatedwithmoney.Shewouldfindawaytohelp.ButSnehadidn’twanttotellherthetruth.

Paragraphl:Snehawenttotheteacher,“Idon’twanttotakepartintheplayandI’mleaving.”

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Paragraph2:Pravinastoodpatiently,waitingfortheperformancetobegin.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________19、阅读下面材料，根据其内容和所给段落开头语续写两段，使之构成一篇完整的短文。IntheGame“I’mgonnaplaybasketball,Daddy.”Mydaughter,Lauren,whooped,skippingintotheroom.“ThereareonlyelevengirlsinVerden,andeverybodymakestheteam.”High-schoolsportsisthebiggestthingthathappensinVerden,soIshouldn’thavebeensurprisedwhenLaurenannouncedshewasgoingoutforthegirls’basketballteams—LadyTiger.ButIwas.MywifeandInevertoldLaurenthatshewasdisabled.Wedidn’twanthertofeeldifferentfromotherchildren.ShehasDownsyndrome(唐氏综合征).Whatiftheothergirlsontheteamfailedtoaccepther?WhatifLaurenspentmostofhertimeonthebench?Whatifshegotinjuredduringthegame?WhatshouldIsaytothecoach?Thenextafternoon,Iparkedbythebasketballcourt.“Hey,Johnny,”CoachForthythecalled.“We’regladLaurencameoutfortheteam.”“Well,Mr.Forthythe,youknowwedon’texpectyoutoplayherinagame.justincludeherwhenyoucan.”ThegamearrivedthenextSunday.Isettledintoaseatonthesecondrowwithmywife.Momentslater,atrainofgirlschuggedoutofthelockerroom.LastinlinewasLauren.Istoodalongwiththecrowdandclapped.Shesearchedthestands.spottedusandwavedbroadly.Thegamegotofftoagoodstart,butsoonVerdenwasbehind.IgazedatLauren,themostexcitedontheteam.Sheslapped(拍打)herkneewhentheopponentsscored.HerarmsmovedaroundintheaireachtimeVerdenshot.Eventhoughshewasn’tplaying,shelookedasifshewerehavingthetimeofherlife.Now,Ifeltadmirationformydaughter.Herteamwasgettingbeat,yetshestillenjoyedtheaction.Justlessthantwominuteswereleft,andVerdenwasdownby17points.Coachcalledatime-out.Thenboomedtheannouncer’svoice,“Numberthirty-three,Lauren,infortheLadyTigers.”

注意：

1.续写词数应为150左右；

2.请按如下格式在答题卡的相应位置作答。Withaslaponherback,CoachsentLaurenrunningontothecourt.

__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________“Didyousee?DadandMum.Iscored!Imadeabasket!”

__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________评卷人得分四、句型转换(共4题，共20分)20、Whenwesawthelakefromthetopofthemountain,itlookedamazing.（用适当的非谓语动词改写句子）

________,thelakelookedamazing.21、Tomisinterestedinscience,soheaskshisDadtotakehimtothesciencemuseumeveryweek.（用适当的非谓语动词改写句子）

________,TomaskshisDadtotakehimtothesciencemuseumeveryweek.22、Whenitisseenfromthehill,thecitylooksmorebeautiful.(同义句转换)

→__________ _____ _____,thecitylooksmorebeautiful.23、Althoughhehadbeenremindedtwotimes,hestillforgothishomework.(同义句转换)

→__________ _____,hestillforgothishomework.评卷人得分五、图画作文(共3题，共30分)24、观察下列三幅图；写一篇短文向英语报社投稿。

内容要点如下：

1.图画内容；

2.你的感受。

注意：

1.标题自拟；

2.词数：80词左右；

3.可以适当增加一些细节；以使行文连贯。

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________25、你在报纸上看到一幅宣传画（如图所示）；对此很感兴趣。请你以此为话题给班级英语角写一篇短文，内容包括：

1.图片内容；

2.个人感想。

注意：

1.写作词数应为80左右；

2.请按如下格式作答。

提示词：树桩treestump

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________26、假设你是李华；为了提高学生的生活技能，你们班上周组织了一次“厨艺秀”。请根据以下四幅图的先后顺序，写一篇英文周记，记录整个过程。

注意：1；词数不少于100；2、开头部分已写好；不计入总词数。

参考词汇：

“厨艺秀”a“cookingshow”activity;家常小炒simplestir-fries;班会课theclassmeetingLastFriday,ourteacherannouncedthatinorderto

_________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________评卷人得分六、概要写作(共1题，共5分)27、Directions:Readthefollowingpassage.Summarizeinnomorethan60wordsthemainideaandthemainpoint(s)ofthepassage.Useyourownwordsasfaraspossible.CitiesintheSeaTheymaybesmall,buttheybuildbigthings!Coralpolyps(珊瑚虫),whichliveinthewarm,shallowpartsoftheEarth’soceans,areprobablythebiggestbuildersontheplanet.Coralpolypsturncalciumfromseawaterintoahardmaterialcalledlimestone.Slowly,theybuildupahardskeleton(骨架)aroundtheirbodies.Whenpolypsdie,theirskeletonsremain.Youngpolypsattachthemselvestotheoldskeletonsandmakenewskeletons.Overtime,weirdandwonderfulshapesareslowlybuiltupintoamazingcoralreefs(珊瑚礁).Scientistssometimesthinkofcoralreefsasunderwatercities.Aquarterofallknownmarinespeciesliveinreefhabitats―therearenearlyathousandcoralspecies.Reefsarealsohometomillionsofseacreatures,likefish,crabs,turtles,andsharks.Humansdon’tliveincoralreefcities,butwebenefitfromthem.Reefscreatejobsforpeopleinthefishingindustryandotherrelatedbusinesses.Coralreefsarealsopopularfordivers一manycountriesbenefitfromthetouriststhattheyattract.Lastly,chemicalsfromreefcreatureshelpscientistscreatenewmedicines,whichhelpdoctorstreatdifferentillnesses.Coralreefsareveryimportant,yetwedon’ttakegoodcareofthem.Environmentalproblemshavealreadykilledabouttwentypercentoftheworld’sreefs.Abouthalfoftheremainingreefsaredying,andexpertsbelieveallofEarth’scoralreefswillbeindangerby2050.Whyarethereefsinsuchtrouble?Foronething,peoplecatchtoomanyreeffishandoftendamagethe