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已知△ABC，点M是边BC的中点，若点O满足，则（ ）
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高三下学期数学《》真题及答案
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已知点O.到△ABC的两边ABAC所在直线的距离相等且OB=OC.1如图1若点O.在边BC上求证AB
在△ABC中已知点A.5﹣2B.73且边AC的中点M.在y轴上边BC的中点N.在x轴上.1求点C.的
如图以△ABC的一边AB为直径作⊙O.⊙O.与BC边的交点D.恰好为BC的中点过点D.作⊙O.的切线
.DE分别是不等边三角形ABC即AB≠BC≠AC的边ABAC的中点.O是△ABC所在平面上的动点连接
已知△ABC点M是边BC的中点若点O满足则
已知如图在△ABC中AB=AC点D.是边BC的中点.以CD为直径作⊙O.交边AC于点P.连接BP交A
如图以△ABC的一边AB为直径作⊙O.⊙O.与BC边的交点D.恰好为BC的中点过点D.作⊙O.的切线
D.E.分别是不等边三角形ABC即AB≠BC≠AC的边ABAC的中点.O.是△ABC平面上的一动点连
O.点是△ABC所在平面内一动点连结OBOC并将ABOBOCAC的中点D.E.F.G.依次连结如果D
已知如图8AD是△ABC外接圆⊙O.的直径AE是△ABC的边BC上的高DF⊥BCF.为垂足.1求证B
如图以△ABC的一边AB为直径作⊙O.⊙O.与BC边的交点D.恰好为BC的中点过点D.作⊙O.的切线
如图已知BC是⊙O的弦A.是⊙O外一点△ABC为正三角形D.为BC的中点M.为⊙O上一点并且∠BMC
已知如图以Rt△ABC的AC边为直径作⊙O交斜边AB于点E连接EO并延长交BC的延长线于点D点F为B
已知如图以Rt△ABC的AC边为直径作⊙O交斜边AB于点E连接EO并延长交BC的延长线于点D点F为B
.D.E.分别是不等边三角形ABC即AB≠BC≠AC的边ABAC的中点.O.是△ABC所在平面上的动
已知如图23212已知△ABC点O.为BC的中点.1画出△ABC绕边BC的中点O.旋转180°得
在Rt△ABC中斜边AC的中点M.关于BC的对称点为点O.将△ABC绕点O.顺时针旋转至△DCE连接
在△ABC中点D.是AB边的中点点E.是AC边的中点连接DE若BC.=4则DE=
已知如图在△ABC中BC=AC=6以BC为直径的⊙O.与边AB相交于点D.DE⊥AC垂足为点E.1求
已知在梯形ABCD中A.D.∥BC∠ABC=90°BC=2ADE.是BC的中点连接AEAC1点F.是
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WeareallfondofCharlie'searlyfilms.Wethinktheyaremoreentertaining.用非限制性定语从句合并 →
假定你是李华你的英国朋友Henry要来中国旅行他来信希望你能给他推荐一个有特色的主题公园.请你给他回信内容包括 1.你的建议上海迪士尼乐园 2.你的理由带你进入魔幻世界遇见自己最喜欢的卡通人物体验刺激的海盗船自由落体每日上演精彩娱乐活动及表演 3.你的祝愿. 注意1.词数80左右 2.可适当增加细节以使行文连贯 3.开头和结尾已给出不计入总词数. 参考词汇海盗船pirateships DearHenry I'mhappytoreceiveyourletterandknowthatyou'recomingtoChina.______ Yours LiHua
Wegotocleangraveslightincenseandsetofffirecrackers为了纪念ourancestorsonTombSweepingDay.
Thankyouforyourvaluableadvicesfromwhichwebenefitalot.
Hisillnesscanaccountfor解释hisnotbeingheretoday．
Waystoimproveyourmemory Thedemandforwaystoimprovememoryishigherinstudentsthanitisinadults.Studentsoftencomeacrossnewknowledgeindifferentareasthattheyneedtostoreforexams.1Herearethreeeffectivewaystoimproveyourmemoryasastudent. ●2 Researchshowsthatlearningactivitiesthattakemorethantwohourswithoutabreakarelessproductivewhencomparedtothosethattakeonehouror30minutes.Studentsarelikelytorememberthingstheylearnoverashortperiodoftime.Makesureyoutakebreaksbetweenlearningsessionstohelpimproveyourmemory. ●Trytorelax Relaxingshouldbeanessentialpartofyourlearningprocess.Scientistshaveproventhatstrongerandlastingmemoriescanbeachievedwhenapersonrelaxes.3Deepbreathingisoneofthemostpopularrelaxationtechniques.Establishaquietenvironmentandfindacomfortableposition.Thengothroughadeepbreathingprocessforatleast15minutes. ●Trainthebrain Studentsshouldgivetheirbrainsaworkoutinordertoimprovetheirmemory.Attimes.thebrainneedstherightstimulationtokeepgrowinganddeveloping.Youneedtocomeupwithabrain﹣boostingactivitythatissuitableforyou.4Writeashortstoryandthentrytouseseventoninewordstodescribeit.Youcanalsodogamesandpuzzlestohelpimproveyourmemory. 5Thetechniquesdiscussedabovewillhelpyoutoimproveyourmemorysignificantly. A.Distribute分散learning. B.Enrichlearningactivities. C.Somestudentssufferwithmemoryproblems. D.Likeamusclememorycanstretchandgrowwithaworkout. E.Forinstanceyoucanpreparealistofitemsandtrytomemorizethem. F.Youneedtousedifferentrelaxationtechniquesinordertoimproveyourmemory. G.Insummaryagoodmemoryisanimportantadvantagetoanystudentwhowantstoimprovehisorhergrades.
Iwouldrather宁愿havethesmallonethanthebigone．
Frommypointofviewthatinterestsmemostistheuniquearchitectureinthiscity.
Manyoftheworld'sfamouscitiesareknownbysomespecialnames.ParisisknownastheCityofLight.HongKongistheWallStreetofAsia.OnesmallcityinPennsylvaniamaybethesweetestplaceonEarth.ThatistownofHersheywhichisknownastheChocolateTown.ItisnamedafterMiltonHersheythefounderofthelargestchocolatefactoryintheworld. MiltonHersheybuilthisfirstcandyfactoryintheearly1900s.AtthetimeHersheywasdevelopingatechniqueformilkchocolate.Eventuallyhesucceeded.Hersheywasalsothefirsttoproduceindividuallywrappedchocolatebars.Hisfactorygrewandproducedmoreandmoretypesofchocolate.TothisdayHershey'schocolatefactoryisthelargestintheworld.Hersheyusedhissuccesstogivebacktothecommunity.Hebuiltatownaroundthefactoryforhisemployees.HegavestreetsfunnameslikeChocolateAvenue.Hebuiltschoolsparksandshops.Thisgenerousmangavemillionsofdollarstocharity.Hebuiltanamusementparkwithridestrainsforchildrenandaswimmingpool.Overtheyearsthetowngrew.Peoplefromnearandfarcametovisitthisspecialtownwhosebeautyandfamecontinuetoattractlotsoftourists.EveryyearclosetothreemilliontouristsvisittheChocolateTown. Todayvisitorstothecitycanenjoyavarietyofattractionsandactivities.TheHersheychocolatefactoryofferstours.Visitorscanlearnallaboutchocolateandhowitismade.Agiftshopsellsallkindsofchocolateandtoysmadetolooklikechocolate.Evenifyoudon'tbuyasouvenirthereisonethingthatisimpossibletoforgetthewonderfularomaoffreshchocolateeverywhere.Inthisspecialplaceeventhestreetlightsareshapedlikechocolate. AnotherattractionistheHersheyHotel.Ithasanunusualmineralspringwhereguestscanenjoyavarietyofspecialtreatments.Thetreatmentsallhaveonethingincommonchocolate. 1WhatcanweknowaboutMiltonHershey? A.Hedislikedtocook. B.Hecaredabouthisemployees. C.Hewantedtobefamous. D.Hedidn'tpayhisemployeesverywell. 2WhatwasMiltonHersheydevelopingwhenhebuilthisfirstfactory? A.Publicstructure. B.Anamusementpark. C.Attractionsforthecommunity. D.Atechniqueformilkchocolate. 3What'sthebesttitleforthepassage? A.MiltonHershey B.World'sFamousCities C.TheChocolateTown D.PennsylvaniaChocolates
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BigchangesinagriculturearetakingplaceinSingapore.ThesmallSoutheastAsiannationisleadingafarmingrevolutionaccordingtotheReutersnewsagency. Singaporecovers724squarekilometersoflandandonlyonepercentofthatlandisusedforagriculture.FoodproductioncostsarehighertherethantherestofSoutheastAsia.Asclimatechangeandpopulationgrowththreatenfoodsuppliesthepressureisonnewfarmerstoanswerthegovernment'scalltogrowmorewithless. Whenever1talkaboutfoodsecurityinSingaporeItellpeopledon'tthinkland﹣thinkspacebecauseyoucangoupwardsandsideways.saidPaulTenganagricultureprofessoratNanyangTechnologicalUniversity. Therearemorethan30vertical垂直的farmsinSingapore﹣onesthatgrowupnotacrosstheland.SustenirAgricultureisoneofthesebusinesses.Itshydroponic水栽法的farmgrowsnon﹣nativefoodslikecherrytomatoesandstrawberriesinsidebuildingsunderartificiallighting.Thenitsellstheproducetolocalsupermarketsandonlinestores.Sustenirraised$16millionfrominvestors投资人lastyear.ThemoneywillbeusedtoexpandoperationsinSingapore. Howevernoteveryonethinksthenewtechnologyisbest.EggfarmerWilliamHosaysthegovernmentshouldnotdependsomuchonagriculturetechnologybusinesses.Manyofthemhavefailed.That'swhyI'malwaysaskingthegovernmentwhydon'tyouinvestinusold﹣timers.Wearemorepracticalhesaid.ProfessorPaulTengsaidanissueforurbanfarmersisthatthehighcostofthetechnologymakestheirproductstoopriceyformanypeople. 1Whatdoesthesecondparagraphmainlydiscuss? A.Highfoodproductioncosts. B.Reasonsforchangesinagriculture. C.Agriculturetechnologybusinesses. D.Saleexpansionoffoodmarkets 2WhatisthewaytoachievefoodsecurityaccordingtoPaulTeng? A.Exploringuptheland. B.Imorefood. C.Enlargingfarmland. D.Investingmoremoney. 3Whatdoweknowabouttheold﹣timers? A.Theyworkonhigh﹣techfarms. B.Theybenefitfrompriceyproducts. C.Theyreduceproductioncosts. D.Theyneedgovernmentsupport 4Whereisthistextprobablytakenfrom? A.Aguidebook. B.Abrochure C.Anewspaper. D.Ajournal
MayIspeakwithJeanneKerr?Isaidcrossingmyfingers. Who'sasking?thevoicerose. It'sReginaLouiseIthinkwemayhavemet. Idon'tbelievesothestrangersaidhangingupthephone. IcrossedoutanotherJeannefrommylonglist.ThefirsttimeImetJeannewasMay11975atEdgarChildren'sShelterwhereIwasdislikedbyallthesocialworkersexceptJeanne. ThelasttimeIsawJeannewasin1977.Iwas15yearsoldstandinginacourtroom法庭askingthecourttoallowJeanneKerrtoadopt收养me.HoweverJeanne'srequesttoadoptmewasrefusedbecauseshewaswhiteand1wasblack.Then1wasplacedinatreatmentcenterfordisturbedgirls. By2002atage401operatedtwosuccessfulhairsalons・Iwroteabookaboutmyearlyteenageyearsfrom13to15astorythatfollowedmethroughmeetingJeanneandlosingher. OneeveningIcheckedmyemailandcameacrossthewordsIamsoproudofyousweetheart!Myheartstopped.IopenedtheemailanditwasfromJeanne.Anoldco﹣workerofhershadreadmybookandcalledJeannetotellherYourReginaislookingforyou. Idialedthenumbergivenintheemailimmediately.Wechattedalotexcitedly.AtlastshetoldmeIwanttomakeyoumydaughter. ThreeweekslaterIstoodinthesamecourtroomwhereJeanne'sfirstrequesttoadoptmehadbeenrefused.AfterthejudgetoldustolivewithandloveoneanotherasmotheranddaughterfortherestofourlivesIturnedtoJeanneandwhisperedThankyou一Mommy一forlovingmewhennooneelsecould. 1WhydidJeannefailtoadoptReginaatfirst? A.BecauseJeanneworkedattheShelter. B.BecauseJeannewasofadifferentrace. C.BecauseReginafoundhermother. D.BecauseReginabehavedbadly. 2WhathelpedReginafindJeanne? A.Thetreatmentcenter. B.Thecourtroom. C.Regina'sbook. D.Regina'shairsalons. 3Whatcanbeasuitabletitleforthetext? A.Iwasadoptedat40. B.Agirl'sroadtosuccess. C.Ifoughtforagoodlife D.Agirl'steenageyears.
AlthoughIhaveconvinced使信服himofmyhonestyIthinkhestillhassomedoubts．
Sallyisagoodstudent.Shedoeswellinallher1subject.Youmustwonder2shecanstudysowell.Letmetellyousomethingabouthergoodstudyhabits. FirstSallyspendstwohours3studyafterschooleveryday.Andshealwaysstudiesfromseventonineonschedule.Sallyisavery4determinegirlsonothingcanstopherdoingthat. SecondifSallywantstostartstudyingfirstshewillputeverything5hasnothingtodowithherstudyingasidelikethecellphone.And6actualthereareonlybooksleftonherdesk. ThirdSallynever7leaveherproblemstillnextday.Whenshemeetssomedifficultproblemsandshecan'twork8theyoutshewillturntoothers9help.Shedoesn'twait10dothemnextday. WhatdoyouthinkofSally'sstudyhabits?Youcanhaveatry.Ihopetheywillbehelpfultoyou.
这座桥300年前是如何建造的仍然还是个谜.用主语从句翻译 →
SharknetsinplaceacrossAustraliaspecificallyinNewSouthWalesNSWandQueenslandtoprotectbeachgoersshouldbedroppedastheyhavecausedmoreharmthangoodastudyhasfound. Themeasureswerecarriedoutbysomegovernmentsincludingnetsandtraditionaldrumlinesandprovidedbeachgoerswithafalsesenseofsafety.Thestudyfoundtheeffectivenessifnetswasdifficulttoevaluatewhilethesignificantdamagetheycausetoothermarine海生的wildlifewasclear.Researchesdesirefornon﹣deadlysharkcontrolmeasuressuchasecobarrierssonar声呐technologyandvariousshark﹣spottingtechniques. Researcherssaidwhiletheriskcomingacrossasharkwasrareanyshark﹣relateddeathsandinjuriescaughthugepublicandmediaattention. Oneoftheargumentsinsupportofusingsharknetsisthatjustoneshark﹣relateddeathhasbeenreportedinQueenslandsincethe1960s.Similarlysincethe1930sNSWhashadonlyoneshark﹣relateddeath.Buttherehavebeenatleast13peoplekilledbysharksatbeacheswithoutnetsintheNSWnorthcoastoverthepasttwoyears. TheHumanSocietyInternational'headofcampaignsNicolaBeynonsaidthegovernmentneededtomoveawayfromoutdatedmethods.Deadlysharknetsanddrumlinesaremorethan50yearsbehindscientificandanimalwelfarestandardsfordealingwithmarinewildlifesaidBeynon. TheNSWGreens'marinespokesmanJustinFieldsaidPeopleare100timesmorelikelytodrownatthebeachthantobekilledbyasharkinAustralia.Thereforemillionsofdollarsgoingintothesharknetprogramshouldbedirectedtoobservationtowersforourlifeguardsandimprovingthebeachdevices. 1Whichofthefollowingdoresearchersfocuson? A.Beachgoers'safety. B.Theshark﹣relateddeathrate. C.Friendlysharkcontrolways. D.Advancedshark﹣spottingtechniques 2Whatisparagraph4mainlyabout? A.Shark﹣relateddeaths. B.Measurestoprotectsharks. C.Reasonsofusingsharknets. D.Dangersforbeachgoers 3WhatdoNicolaBeynonandJustinFieldhaveincommon? A.Scienceisdevelopingtoofast B.Observationtowersneedrebuilding C.Manypeoplearedrowneveryyear. D.Nosharknetsaretobeused. 4Whatcanbethebesttitleforthenext? A.Aresharknetsnecessary? B.Anewstudyonseaanimals C.Sharknetprograms D.Effectivewaysofavoidingsharks
Tomdecidedtotalktohisteacherwiththehopeofpersuadinghertogivehimahigherscore.用非谓语动词改写 →Tomdecidedtotalktohisteacherhertogivehimahigherscore.
假定英语课上老师要求同桌之间交换修改作文请你修改你同桌系的以下作文.文中共有10处语言错误每句中最多有两处.错误涉及一个单词的增加删除或修改. 增加在缺词处加一个漏词符号∧并在其下面写出该加的词. 删除把多余的词用斜线\划掉. 修改在错的词下划一横线并在该词下面写出修改后的词. 注意1.每处错误及修改均仅限一词 2.只允许修改10处多者从第11处起不计分. AcharitysalewasheldinourschoolplaygroundinlastSunday.Wepreparedmanythingsmakingbyhandsuchaskitesandmodelplanes.Wealsobroughtoldtoysorsecond﹣handbookstosell.Whentheactivitystartedlotsofstudentsparticipatedinthemandchosetheirfavoriteitems.Inendwemade2000yuaninall.Wedonatethemoneytothecommunitytohelpchildrenwhocouldn'tattendschool. Ihadawonderfullyexperience.Iamproudofwhichwehavedone.Ifeveryonemakesacontributionforthecharitytheworldwillbecomemuchgoodthanitusedtobe.
ConfidenceinMathsConfidenceforLife． ChangingLivesThroughMaths! MathnasiumofNorthOxfordyourneighbourhoodmaths﹣onlylearningcentre! Wehelpchildrenaged13一18understandmathsinaspecialway．OurwayofteachingchildrenmathstheMathnasiumMethodhaschangedthewaystudentslearnmathsforoveradecadeacross800+centresworldwide •Weknowhowtoteachyourchildmaths． Ourspeciallytrainedmathsteacherswillteachyourchildhowtounderstandmathsinaspecialsetting﹣ouruniqueapproachenablesustoeffectivelyexplainmathsconcepts概念wellandlendahelpinghandtoeverystudent．Ourteacherscreateacaringencouragingenvironmentthathelpsyourchildcatchupkeepupandgetaheadintheirmathslearning． •Wefindexactlyyourchild'slearningneedsmeetthemwheretheyareandtakethemwheretheyneedtogo． AtMathnasiumweuseouruniqueassessmentprocess评估过程todetermineexactlywhateachchildknowsandwhattheyneedtolearn．Nextwedesignanindividual单独的learningplanforeachstudent．Itdoesn'tstopthere﹣ourteacherscontinuallycheckprogressalongthewaytomakesurestudentstrulyunderstandtheconceptswe'vetaught．Studentslearnmathsattheirownspeedandaccordingtotheirownlevel．Theywillseeobviouschangesinattitudeconfidenceandschoolprogress． AboutOurCentre Sinceitsopeningon8SeptemberthisyearMathnasiumofNorthOxfordhasbeenofferingmathsinstructionandhomeworkhelptostudentsinthecommunity．Youcanfindusat18SouthParadeSummertownNorthOxford0X27JL Callat01865855968ore﹣mailtomathnasium．co．uk． HoursofInstruction Weekdays330PM﹣730PM Weekends900AM一500PM Click点击heretofindoutifMathnasiumisrightforyourchild． 1WhomdoesMathnasiumofNorthOxfordteachmathsA A．Teenagers． B．Adults． C．Babies． D．Graduates． 2WhatisspecialaboutMathnasiumofNorthOxfordC A．Itslarge﹣sizedclasses． B．Itslocation． C．Itsindividualteaching． D．Itsschoolenvironment． 3MathnasiumofNorthOxfordisopenonthemorningof．D A．Mondays B．Tuesdays C．Thursdays D．Saturdays 4WherecanyoufindtheadC A．Inthenewspaper． B．Ontheposter． C．OntheInternet． D．Overtheradio．
假定英语课上老师要求同桌之间交换修改作文请你修改你同桌写的以下作文．文中共有10处语言错误每句中最多有两处．每处错误仅涉及一个单词的增加删除或修改． 增加在缺词处加一个漏字符号Λ并在其下面写出该加的词． 删除把多余的词用斜线\划掉． 修改在错的词下划一横线并在该词下面写出修改后的词． 注意1．每处错误及其修改均仅限一词 2．只允许修改10处多者从第11处起不计分． Mr．Gaolivesnexttomyhome．Heisateacher．HeteachesPEinafamousmiddleschoolwhereisoneofthekeyschoolinourcity．Hehasbeenteachingtherefortenyears．Heisverypatientonhisstudentsandhislessonsareinterestedandlively．Asaresultheishighlyappreciatedbyhisstudents．Heoftentellsthempayattentiontoourhealth．Andheasksthemtoworkoutregular．HissonGaoBowasmygoodfriendandweoftenstudytogether．SometimesMr．Gaoplaysthebasketballwithusafterschool．Insummerheoftentakesustotheswimmingpoolorteachesustoswim．
Iwillratherstayathomereadingthangooutshoppingwithyouonsuchahotday.
Jacquelinausedtoweighover500pounds.Andforyearsshe1towearabathingsuit. Sherealizedherlifeneededacomplete2afteranunpleasantexperienceatDollywoodwhereshegot3inaturnstile旋转式栅门.ThenJacquelinadecidedtomakeachange.Shewasgoingtogetcontrolofher4! Ofcourseitwasnoeasytask.Shedevotedyearsto5withdoctorseatingrightandexercising.And6herhardworkJacquelinalost350pounds・ YearslaterJacquelina7toMexicoforavacation.Havinglost350poundsshedecidedshewasreadytowearabathingsuitwithouta8Iwas9totakemycover﹣upoffandwalkintothepool.Istillfeltlikethatsame500poundgirl.Jacquelinaexplained. ButJacquelinawasreadytofaceherfears.10.peoplearoundhercruellypointedand11atJacquelina. InthepastIwould12theircommentstoaffectmyvacationandIprobablywouldnevergotothatpoolagain.shesaidtoherself. 13nowshe'sachangedwoman! Insteadoflettingtheirresponsebringher14.shetookadeepbreaththenchoseto15andwalkintothepool. Thatwasahuge16formeshesaid.Ihadchanged.Iwasnotthe17girlanymore. Whileshe'dlost350poundsitwasn'tjustJacquelina'sbodythathadchanged.Her18changedtoo.Cruelcommentsstill19.butsherealizedherworthhad20todowithwhatotherpeoplethought. 1A.tried B.refused C.agreed D.liked 2A.stop B.hug C.change D.mixture 3A.stuck B.lost C.buried D.punished 4A.touch B.weight C.sight D.thought 5A.arguing B.bargaining C.chatting D.consulting 6A.ratherthan B.incaseof C.becauseof D.insteadof 7A.slid B.wandered C.headed D.escaped 8A.shirt B.cover﹣up C.hat D.decoration 9A.excited B.bored C.willing D.nervous 10A.Sadly B.Hopefully C.Hurriedly D.Calmly 11A.glared B.waved C.aimed D.laughed 12A.forgive B.allow C.persuade D.direct 13A.Though B.Since C.And D.But 14A.down B.up C.forward D.out 15A.pack B.entertain C.smile D.turn 16A.moment B.failure C.comment D.gesture 17A.shy B.same C.silly D.slim 18A.appearance B.style C.figure D.mind 19A.swung B.mattered C.hurt D.helped 20A.nothing B.something C.anything D.everything
Ittookmequitesometimetosettledowninthevillageandgetclosethelocalpeople.
Whenpeopleseemachinesthatrespondlikehumansorcomputersthatperformamazingfeatsofstrategytheysometimesjokeaboutafutureinwhichhumanitywillneedtoacceptrobotoverlords.Butburiedinthejokeisaseedofunease.SciencefictionwritingandpopularmovieshaveshownusaboutartificialintelligenceAIthatexceedstheexpectationsofitscreatorsandescapestheircontroleventuallyoutcompetingandenslavinghumansortargetingthemforextinction灭绝.EvenintherealwordnoteveryoneisreadytowelcomeAIwithopenarms.InrecentyearsascomputerscientistshavepushedtheboundariesofwhatAIcanaccomplishleadingfiguresintechnologyandsciencehavewarmedaboutthefrighteningdangersthatartificialintelligencemayposetohumanityevensuggestingthatAIcapabilitiescoulddestroythehumanrace.ButwhyarepeoplesofrightenedabouttheideaofAI?ElonMuskisoneofthefamousvoicesthathaveraisedredflagsaboutAIInJuly2017.MusktoldattendeesatameetingoftheNationalGovernorsAssociationIhaveexposuredtotheverycutting﹣edgeAlandIthinkpeopleshouldbereallyconcernedaboutit.Ikeepsoundingthealarmbell.Butuntilpeopleseerobotsgoingdownthestreetkillingpeopletheydon'tknowhowtoreactbecauseitseemssoimpossible.'Earlierin2014MuskhadlabeledAI'ourbiggestexistentialthreat'andinAugust2017hedeclaredthathumanityfacedagreaterriskfromAIthantheterrorists.PhysicistStephenHawkingwhodiedonMarch14alsoexpressedconcernsaboutAItellingtheBBCin2014that'thedevelopmentoffullartificialintelligencecouldspelltheendofthehumanrace.1WhataretopscientistsinAIworriedabout?A.Itsabilityofimpressivefests.B.Itcontributestoomuchtomovies.C.Itmayendthehumanracesomeday.D.It'scapabilitytoburyourseedsinjokes.2Whatis'redflags'inparagraph4?A.Questions.B.WarningsC.Complaints.D.Wonders.3InStephenHawking'opinionAIcould.A.beagreatthreattohumanbeings.B.learnthehumanemotionslikefear.C.predictthefutureofthehumanrace.D.composehorribletalesintoscarystories.4Thetextisprobablytakenfromaresearchpaperin.A.TechnologyB.HealthC.Planetearth.D.Humannature.
JustasaChinesesayinggoesathousand﹣milejourneystartwithasinglestep.
TwoyearsagoIwasatypicalgirlwitharatherplainlife.When1toalocalvoluntaryorganizationcalledPeer﹣to﹣PeerbyaposterIhadnoideawhatthisgroupwasabout.2tolearnmoreaboutitIdecidedtoattenda3whichchangedmylife. Justlikethe4suggestseveryoneisconsideredapeerincludingregularmembersandourleaders.Thismeanswecan5ourleadersbytheirfirstnames.Wecanalsoaskourleadersforhelpin6lifesituationswhichweknowtheywillnever7!Whenitcomestoconversationsaboutawkwardtopicslikeloveweare8nottobeashamedofourselves. Thisorganization'smeetings9inourlocallibrary.Weusuallygatherandcommunicateabout10topicsconcerningoursocietyeducationequalityandsafety…Thiskindofcommunicationhelpsustomaketherightchoiceand11ourmind.Sometimeswe'vegoneoutsideinordertoparticipatein12events.Oneeventwehad13wasGiveacigarette﹣Takeacandyintendingto14smoking. Atthisorganizationwearefriendswitheachotherandarea15community.I'vealsogainedalotof16experiencebycommunicatingwithpeopleandworkingintheteam. WithtimegoingbyIhavefoundanabundanceofother17organizationssuchasGiveGoodandYouthInitiativeCenter.Allofthemhave18meagreatchancetodevelopmyownpersonalityandmakemylife19. I'msureI'llhavealotofwonderful20aboutmyyouthwithmegettingolder. 1A.invited B.transformed C.promoted D.introduced 2A.Besides B.Accidentally C.Therefore D.Luckily 3A.party B.meeting C.competition D.program 4A.name B.poster C.aim D.organization 5A.address B.assist C.inform D.avoid 6A.simple B.difficult C.familiar D.similar 7A.accept B.understand C.realize D.reject 8A.forced B.requested C.encouraged D.reminded 9A.carryon B.takeplace C.setdown D.turnup 10A.light B.rare C.hot D.plain 11A.broaden B.correct C.polish D.support 12A.powerful B.cheerful C.hopeful D.meaningful 13A.inshort B.asusual C.forexample D.ineffect 14A.criticize B.spread C.decrease D.ignore 15A.famous B.tight C.workable D.good 16A.original B.particular C.potential D.precious 17A.voluntary B.individual C.professional D.social 18A.cost B.guaranteed C.owed D.prepared 19A.irregular B.comfortable C.attractive D.unbelievable 20A.memories B.impressions C.secrets D.dreams
BlackholeswerefirstputforwardbyAlbertEinsteinin1916．Howeverscientistshadnotprovedtheirdirectly．ThatchangedonApril102019withthereleaseofthefirstphotoofablackholeinthecenterofthegalaxy星系M87located55millionlightyearsfromEarth． Thephotodoesnotshowtheblackholeitself．That'sbecausetheyareblackandsotheycan'tbeseeninspace．thescientistsusedradiosignalstocapture拍摄theblackhole'sshadow﹣thebrightringthatformsarounditsedgewhenlightbendsbecauseoftheextremegravityaroundthehole． TheM87blackholebelievedtohaveamass6.5billiontimesthatofoursunwascapturedusingtheEventHorizonTelescopeEHT﹣anetworkofeightpowerfultelescopes望远镜ThetelescopeslocatedinHawaiiArizonaChileMexicoSpainandAntarcticaseparatelycapturedtheblackholl'sradiosignalsoverfournightsinApril2017whentheweatherwasfineinallsixplaces．Thedatawastransporiedtoacentrewhereitwasdealtwithbyasupercomputertoformthephotooftheblackhole'sshadow．TheresearcherssaywhilethephotoisslightlyblurryfuturephotoswillbeclearerasmoretelescopesareaddedtotheEHT．Blackholesarenoteasytocaptureoncamerabecausetheyaresurroundedbythickdustyandhotgases． Blackholesareareasinspacewherethepullingstrengthofgravityissopowerfulthatevenlightisunabletoescape．Theycanbedifferentwidelyinsizeandmass．Thesmallestcalledprimordialblackholesareassmallasasingleatombutwithamassofabigmountain．Stellar''blackholeswhicharethemostcommonhaveadiameter直径ofabout10milesandamass20timesthatofoursun．Thelargestorsupermassive''blackholessimilartothatofM87'scanhaveamassgreaterthanmillionsorevenbillionsofsunscombined． 1WhatcanweinferfromthefirstparagraphA A．Einstein'spredictionaboutblackholesisright． B．Einsteincapturedtheblackholeacenturyago． C．Scientistshaven'tprovedblackholes'presence． D．Theblackholehasbeenknownforcenturies． 2Whatdidthescientistsusetocapturetheblackhole'sshadowC A．Moonlight． B．Naturallight． C．Radiosignals． D．Soundwaves． 3WhatdoestheunderlinedwordblurryinthethirdparagraphprobablymeanB A．Notbig． B．Notclear． C．Notnew． D．Notattractive． 4WhatcanweknowabouttheM87blackholeD A．Itisalmostempty． B．Itisthesmallestone． C．Itisverybright． D．Itisverylarge．
LikemanylanguagesspokenbypeopleAyapanecoisdying.Onlytwopeopleintheworldstillspeakitandtheywon'ttalktoeachother. SpokeninMexicoforcenturiesAyapanecoisoneof68survivinglanguagesinthemainlySpanish﹣speakingnation.ThetwospeakersareManuelSegoviaandIsidroVelazquez.Thoughtheyliveonly500metersfromeachotherinthevillagethetwomenseldomtalktoeachother.DanielanAmericanexpertwhoisworkingtomakeadictionaryofAyapanecosaysthetwomendon'thavealotincommonandthatSegoviacanbeactivewhileVelasqueztendstomindhisownbusinessandstayathome. WhileSegoviastillspeakstohiswifeandsoninAyapaneconeitherofthemcanmanagemorethanafewwords.Velasquezhardlyspeakshisnativetongueanymore.Danielisworkingtoprotectthelanguageindictionaryformbeforeitslastsurvivingspeakerspassaway.AccordingtoDanielAyapanecoandtheotherlanguagesbegandyingoutwiththeintroductionofpublicSpanisheducationinthemid﹣20thcentury.Fordecadeslocalchildrenweren'tallowedtospeakanythingelse.Manypeopletocitiesstartinginthe1970salsohelpedthedyingoutofnativelanguages. AyapanecoisthenamegiventothelanguageSegoviaandVelazquezcallitNuumteOotewhichmeanstruevoice.Neithermanhoweverspeaksthesamelanguage.Thedictionarywillcontaintwoversions版本ofthelanguagewhenitcomesoutlaterthisyear.Thosebehindthedictionaryaren'ttheonlyonestryingtosaveAyapaneco.TheNationalLanguageInstituteplanstoholdclassessothatSegoviaandVelasquezcanpassonwhattheyknowtochildren. Itisthoughtthatthereareabout6000languagesspokenonearthandthatabouthalfwilldisappearoverthenext100years.Let'shopethetruevoiceisn'toneofthem. 1SegoviaandVelasquezseldomtalktoeachotherinAyapanecobecausethey. A.bothdislikethelanguage B.don'tgetalongwellwitheachother C.aretoobusytotalktoeachother D.don'tsharethesameinterests 2WhicharethemainreasonswhythelanguageAyapanecostarteddyingout? a.Noteacherlikedtoteachit. b.LocalchildrenhadtospeakSpanish. c.Thesurvivingspeakersdidn'tliketouseit. d.Manyvillagerswenttoliveincities. A.ab B.ac C.bd D.bc 3HowdoestheNationalLanguageInstitutetrytosaveAyapaneco? A.WriteadictionaryofAyapaneco. B.LetAyapanecobetaughtatschool. C.IntroduceapublicAyapanecoeducation. D.AskvillagerstospeakAyapaneco. 4Fromthetextwelearnthattheauthor. A.agreesthatitisnaturalthatAyapanecoshoulddieout B.thinksDaniel'sefforttopreserveAyapanecowon'twork C.thinkshighlyofAyapanecoandwantspeopletolearnit D.hopesthatAyapanecowillnotdieoutinthefuture
OnMarch102019eight﹣year﹣oldTanitoluwaTaniAdewumibeat73youngcompetitorstowintheNewYorkStateChessChampionshipinhisagecategory﹣kindergartentothirdgrade．Whilethe1Bisgreatwhatisevenmoreamazingisthattheboy2Alearningthegamelessthanayearago． Taniandhisfamily3DinNewYorkCityfromNigeriain2017．SoonafterTanistartedtostudyatthe4BelementaryschoolP．S．116whichisnearhishome．Itwasherethattheyoungboywasfirst5Atothechess．6CbythegametheboybeggedhismotherOluwatoyintoallowhimto7Ctheschool'schessclub．Consideringthatthefamilywouldbeunabletoaffordthe8DOluwatoyinemailedchess9A．RusselMakofskywhorantheclub．Tohersurpriseand10BMakofskyagreedtochargeyoungTaninothing．Theyoungboymadeuphismindtopracticeharderinreturnforhis11CHehaswonsevenimportantprizesinlessthanayearand12D#27inAmericainhisagecategory． 13CthechessclubcertainlyhelpsTani'ssuccesscanbelargelyowedto归功于his14Atothegame．Thechessplayer15Bthegameforseveralhoursaday．EverySaturdayTaniandhismother16DtoHarlemforafree3﹣hourclasstohelpfurthersharpenhisgameskills． Heisnowbusy17AtheNationalElementaryChampionshipswhichwillbeheldinNashvilleTN．Winningthe18Dwillbringthechessplayerclosertohisdreamofbecomingtheworld's19Cchessgrandmaster大师．TherecordisnowheldbyRussianchessplayerSergeyAlexandrovichKarjakinwhowonthetitlein2002attheageof12years．Wehaveno20Athatthedeterminedboywillachievehisgoalsoon! 1A．agreement B．achievement C．treatment D．argument 2A．began B．enjoyed C．missed D．minded 3A．stayed B．worked C．lay D．arrived 4A．religious B．local C．strict D．distant 5A．introduced B．compared C．invited D．directed 6A．Confused B．Encouraged C．Attracted D．Beaten 7A．found B．run C．join D．visit 8A．bills B．trips C．meals D．fees 9A．teacher B．customer C．learner D．farmer 10A．sadness B．happiness C．puzzlement D．anger 11A．rescue B．wish C．help D．service 12A．loses B．sets C．has D．ranks 13A．If B．Unless C．Though D．Because 14A．devotion B．action C．reception D．return 15A．appreciates B．practices C．watches D．creates 16A．return B．lead C．point D．head 17A．preparingfor B．waitingfor C．caringfor D．searchingfor 18A．friendship B．war C．praise D．competition 19A．smallest B．strongest C．youngest D．tallest 20A．doubt B．wonder C．problem D．sign
Theletterwasnotaddressed写地址tomebutIopeneditoutofcuriosity好奇．
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