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已知关于x的方程x2+3x﹣m＝0有两个相等的实数根，则m的值为 ．
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MyclosechildhoodfriendHowardAllenbroughtusgoodnews.Hespentthelasteightyears1nightschooltogethisbachelor'sdegreewhileworkingafull﹣timejob.Afteryearsoflate2andweekendsofdoingcourseworkandstudying3hegraduatedlastmonth. Heremainedinourhometownafterhighschoolbutmostofhis4myselfincludedleftour5tootherstatesforuniversityandemployment.Overtimenewfoundresponsibilitiesfamiliesandotherthingshavemadeit6thatwe'rebackinourhometownatthesametime. Oneofourmutual共同的friends7awonderfulidea.Wemadeaweekendplanthat8we'dallflybacktoourhometownto9himandcelebratehisaccomplishment. Wecontacted联系Allen'smomand10howtohaveAllencometothesurprise11party.Wedecidedthathismomtoldhimthathewasgoingtohavedinnerwithjusthis12tocelebrate.Littledidheknowthatthedinnerwould13a20﹣personaffairwithhisoldfriendspresentfromalloverthecountry!MeanwhileAllenlikescakesverymuchandI14abigonewhoseflavorwashis15whichIknewfrommychildhood. WhenAllen16tohavedinnerwithhisgrandparentshewas17surprisedandmoved.Hetoldushowmuchit18tohimthatweallflewintomakehimfeel19.Itwasobviousthatthepartywasagreat20butthatwaswhatweshoulddo.Asisoftensaidwhateverisworthdoingatallisworthdoingwell. 1A.building B.attending C.repairing D.cleaning 2A.days B.mornings C.afternoons D.nights 3A.finally B.quickly C.strangely D.naturally 4A.sisters B.brothers C.friends D.teachers 5A.office B.hometown C.company D.job 6A.famous B.rare C.familiar D.fun 7A.liked B.remembered C.hatched D.knew 8A.insecret B.byluck C.inreturn D.bychance 9A.invite B.find C.surprise D.face 10A.showed B.answered C.watched D.discussed 11A.Christmas B.birthday C.graduation D.business 12A.relatives B.grandparents C.colleagues D.classmates 13A.turninto B.gothrough C.dealwith D.careabout 14A.discovered B.received C.drew D.ordered 15A.favorite B.plan C.dream D.design 16A.stopped B.arrived C.waited D.expected 17A.totally B.frankly C.suddenly D.normally 18A.described B.explained C.suggested D.meant 19A.calm B.confident C.brave D.special 20A.invention B.devotion C.success D.medal
TheChinesePeople'sLiberationArmyNavyturned70onApril232019.Itisatimeforreflectingonitsbeginningandhowoverthepastsevendecadesithasovercomesomanydifficultiestogrow1amodemnavalforce. AsamajorPacificcountry2hasmorethan18000kilometersofcoastlineChinaneedsapowerfulnavalforcethatcantimelyrespondtochallengesandrisks.ThePLANavyisincreasinglybeinglookeduponasanessentialforce3defendthecountry'sinterestsandprotectitsnationals'personalsafetyand4possessionoverseas. ThusthecallsforChinatobuildablue﹣seanavyhavebecomestronger5thePLANavyhasapparentlyaccelerateditsmodernizationstepstryingtoincreaseitsbattleabilitiesandreadiness.Nottomentionthatthenavyalsohasthedutytomore6effectiverespondtochallengestothecountry'smaritime海上的interestsandterritorialintegrity领土完整. HoweveraspartofChina'sdefenseforcesthePLANavyisaforcefor7peacepurposesThePLANavyhasalsoactivelyparticipatedininternationalhumanitarianmissions使命and8conductvariousexchangeswithnavalforcesfromothercountriestobuildunderstandingand9strengthtrust. SowehavereasontobelievethatthePLANavy10contributebettertoworldpeaceanddevelopment.
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Ihavebeenluckyenoughtoberightnexttodolphinsplayinginperfectsurfusingthepowerofthewavestotravelevenfasterthantheynormallyswim.ThereisnodoubtthattheyareenjoyingthemselvesandthoughIcan'tswimlikeadolphin1. Bodysurfinginvolvesridingonawavewithnohelpfromanydevice装置suchasasurfboardwhichmakesitthepurestformofsurfing.Infactitisoneofveryfewextremesports﹣freeclimbingandcliffdivingareothers2. Howeveritismoreenjoyableandsaferifyouuseflippers脚蹼.Thisisbecausetheyenableyoutoswimfasterandsocatchwavesandsurfalongthemmoreeasily.3Anotheraidisahandboardamini﹣surfboardaboutthesizeofanironheldinonehandtogeneratemorespeedalongthewave. Tocatchawaveswimtowherethewavesbreakandasoneapproachesstartswimmingtowardsthebeach.Youmusttrytotravelatthesamespeedasthewaveandifyoudoitcorrectlyyouwillfeelthewaveliftingyouandpushingyouforwards.4 Bodysurfingisnotaprofessionalsport5thePipelineBodysurfingClassic﹣﹣heldeachyearatthelegendaryBanzaiPipelineinHawaii.LocalbodysurferscompeteagainstathletesfromplacessuchasAustraliaBrazilJapanorFranceinterrifyingwallsofwaterabovethesharpcoralreef. Formenoothersportisasmuchfunasbodysurfing.There'sagoodreasonwhydolphinschoosenottousesurfboards! A.Thentryandsurfalongthesurfaceofthewave B.Icanexperiencethissamefunwhenbodysurfing C.butitdoeshaveitsownunofficialworldchampionship D.thatcanbepractisedbyusingnothingbutthehumanbody E.whichislookeddownonbyprofessionalathleteshowever F.Famousbodyboardersinthegreatsurfinghistoryhavealsocompeted G.Awetsuitisalsoadvisabletouseunlessyouarebodysurfingintropical热带的seas
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假定你是李华你的新西兰笔友CharLie打算今年7月到中国旅游他发邮件向你询问有关情况请根据以下要点用英语给他回复. 1.髙铁飞机等方便快捷; 2.人脸识别即可进入景区; 3.无现金支付随处可用. 注意: 1.词数10左右; 2.可以适当增加细节以使行文连贯; 3.开头和结尾已为你写好不计入总词数. 参考词汇:人脸识别facialrecognition HiCharLie _____ Yours LiHua
KindleE﹣reader8thgeneration FreeTouchscreenDisplay Price:﹩79.99 ●Thinandlightforone﹣handedreading NewKindleis11%thinnerand16%lighterthanthepreviousgenerationKindlemakingiteasyandcomfortabletoholdinonehand. ●ReadlikerealPaper Kindlecreatestextsimilartowhatyouseeinaphysicalbook.Theblacksandwhitesonthescreenareuniformimprovingtextandimagequality. ●Long﹣lifebattery Kindledoesn'tneedpowertoshowapageoftextallowingyoutoreadforweeksonasinglecharge. ●Thousandsofbooksnodistraction分心 Kindleisdesignedtobeane﹣reader.Itsatisfiesyourloveofreadingwithoutinterruptionslikee﹣mailsandphonecalls. ●Lookitupwithoutleavingyourpage SmartLookupcombinesentriesfromTheNewOxfordAmericanDictionarywithinformationfromWikipediasoyoucanknowmeaningscharactersandmorewithoutlosingyourplace. ●Adjustyourtextsize Choosefromeighttextsizestopreventtiredeyessoyoucankeepreadinglonger. Customerreviews: ※DamonMay212019 Thepriceisgreatwithanextra﹩20offandthisnewKindleissmallerinmyhandsthanmyoldone.IwassadtolosemyoldKindlebutthisoneisterrific. ※JasonJanuary262019 ImisstheoriginalKindlerssize﹣thisoneistoosmall.Alsothescreenisoverlysensitiveandthingspopup弹出andthebatterydoesn'tlastaslongastheoriginalKindle.ButmybiggestdisappointmentisthatthisKindledoesn'tallowyoutotransfereverythingfromtheoriginalKindlesoIlostalloftheinformationfrommyoldone.Overalldisappointing. ※SusanNovember172018 IhadtheoriginalKindleandthebatterylastedforweeks.Thisbatteryonlyseemstolastafewdayshowever.TheotherproblemIhavewiththisversionoftheKindleisthetouchscreen.Itisannoyingwhenyouarereadingandstartturningthewrongway.Sometimesit'shardtogetthepagetoturnthewayyou'dlikeitto. 1Whichisafeatureofthe8th﹣generationKindle? A.Itis16%thinnerthanthepreviousone. B.Itisuser﹣friendlywithabuilt﹣indictionary. C.Itcanrunforseveralmonthsonasinglecharge. D.Itisdesignedtoreceivee﹣mailsandmakecalls. 2InwhichwaydoesJason'snewKindlebotherhimmost? A.Itsscreenismuchtoosensitive. B.Itisnotaslargeasheexpected. C.Itsbatterylifeisn'taslongashisoriginalone. D.Documentscan'tbetransferredbetweendifferentKindles. 3WhatproblemdoJasonandSusanhavewiththeirnewKindle? A.Therearealwaysmessagespoppingup. B.Ifsdifficulttoturnonthetouchscreen. C.Pageturningdoesn'tworkwellsometimes. D.Thebatterylastsshorterthantheoriginalone.
Parrotshavebeenknowntomimicwordsbuthaveyoueverthoughthowtheycommunicate?Thesoundstheymakemaysoundmeaninglesstousbutnewresearchhasfoundthatwildparrotsareactuallygivennamesbytheirparents. AccordingtoastudyledbyKarlBergofCornellUniversityintheUSnestlings雏鸟aregivenauniquesoundoftheirownwhichstayswiththemfortheirentirelives. Inthestudytheteamplacedhiddencamerasinthenestsof17differentwildparrots.Afterstudyingtheirsoundstheteamfoundslightdifferencesinthecallsparentsusedtocommunicatewitheachchick.Andevenbeforethenestlingshadlearnedtocommunicateproperlythebabybirdsseemedtorecognizeandmimictheircalls. Soundsverysimilartohumansdoesn'tit? Thestudyalsoprovedthatthesesignaturecallsareacquiredsociallynotgenetically.Todothisscientistsswitchedtheeggsinnineofthe17nestssothathalfoftheparrotswereraisingnestlingsthatwerenottheirs.Usingtherecordingsthescientistsconcludedthenestlingsallusednamessimilartothosetheparentswhetherbiologicalornonbiologicalcalledthemforthefirstweeksoftheirlives.LucieMcNeilfromNationalGeographicsaidthiswouldbethefirstprovenexampleofanon﹣humanspeciesteachingacoustical声学的communication. LeadscientistforthestudyKarlBergtoldNationalPublicRadiooftheUSMostpeoplesay‘Wellallthosecallsarejustnoise'butIthinkthey'rehavingconversations. WhenaskedwhatelsetheparrotsmightbesayingBergrepliedThetheoryisthatthesebirdsaredecidingwherethefoodis.Dowewanttogo3kmNorth﹣northwest?Dowewanttogotothatfield?'Theyaresortofarguingordiscussing.NaturalscienceauthorVirginiaMorellwrote:Verygraduallyscientistsarelearningtounderstandtheconversationsofverydifferentanimalsthatlivelivesrichwithplansquarrelsandromance. Youneverknowifthescienceofanimaltranslationkeepsadvancingwemightonedaybewatchingarealityseriesaboutparrots. 1Whatdidthenewresearchfindaboutwildparrots? A.Theycantalkbylearningfrompeople. B.Thesoundstheymakearemeaningless. C.Theyhavenamesgivenbytheirparents. D.Theyhaveauniquewayofmakingsounds. 2Whichofthefollowingmaythescientistsagreewith? A.Differentparrotsarecalleddifferentlybythetheirparents. B.Babyparrotscantellwhotheirbiologicalparentsare. C.Babyparrotscanmimictheirbiologicalparents'callsbetter. D.Parrotsarethemostskilledanimalsinacousticalcommunication. 3Whydidthescientistsswitchtheeggsinthestudy? A.Toseewhethertheparentscouldrecognizetheirownbabies. B.Toseewhethertheparrotsmadethesamesoundsalltheirlives. C.Toseewhetherthesignaturecallswereacquiredsociallyorgenetically. D.Toseewhetherbiologicalandnonbiologicalparentsnamedbabiesdifferently. 4Whichofthefollowingisthebesttitleofthepassage? A.AnewresearchintheUS B.Parrotscanreallytalk C.Conversationsofanimals D.Parrotsmakemeaninglesssounds
Arubaisoneofthemostwell﹣knownCaribbeandestinationsfortouristsaroundtheworld. You'reprobablywonderingwhattoincludeaswellaswhattowearwhileyou'reinAruba. Clothes Themainreasonwhyyou'reheadingthereistorelaxonthecountry'sfreshbeachesandjoyinwarmwatersoftheCaribbeanSea.Duringmostofthedayyou'lllikelybewearingyourswimsuit.Whenyou'refinishedatthebeachorpoolareaitisadvisabletobringalongashirtorcoveraswellasshortstowear. Itisnotrecommendedtowearbeachclotheswhenyougooutfordinner﹣regardlessofthetimeofday.ShortsandT﹣shirtsareenoughinmanyrestaurantsalthoughmoreformalclothesareadvisedforthefanciesteatingestablishments. Whatelsetobring? TheCaribbeansunisverystrongandifyou'replanningonspendinglotsoftimeinthesunthereareseveralprecautionsyoumusttake.Includesuncreamsunglassesawidehatacoupleofbathingsuitsaswellasabeachbagandacoolerinyourluggage. WhatNOTtobring? WhiledrinkingwaterisquestionableornotsafeinmanyCaribbeannationsArubaisanexception.Arubaisknownforhavingthecleanestwaterintheworld.Thereisnoneedtobringwatersimplybringalonganemptybottle. SeveralitemsareprohibitedinArubaforcarrying.Theseincludefirearmse﹣cigarettesaswellassharpobjectsandtools. 1TouristschooseArubaforadestinationmainlybecause. A.theycanwearcasualclothesfreely B.theycanenjoythebeautifulscenery C.theycanrelaxonthebeachandinwaters D.theycanhaveawonderfuldinnerpartythere 2WhichofthefollowingisnotadvisedtodoinAruba? A.WearingaT﹣shirtinarestaurant. B.Preparingsuncreaminadvance. C.Wearingbeachclothesfordinner. D.Takingalongsunglassesbeforegoingout. 3Thepurposeofthetextisto. A.provideinformationfortourists B.offeradviceontravellinginAruba C.attractmoretouriststotravelinAruba D.warntouristsagainstdoingwrongthings
Everyyearwildfiresdestroymillionsofhectaresofforestland.1Smokejumpershelptostopthis. 2Smokejumpersareaspecialtypeoffirefighter.Theyjumpfromplanesorareloweredbyhelicoptersintoareasthataredifficulttoreachbycaroronfootsuchasthemiddleofamountainforest.Theyracetoputoutfiresasfastastheycan. Atafiresitesmokejumpersfirstexaminethelandanddecidehowtofightthefire.Theirmaingoalistostopafirefromspreading.Usingbasicequipmentsuchasshovelsandaxessmokejumpersclearlandofburnablemateriallikeplantsandotherdrymaterial.3 Althoughthemajorityofsmokejumpersaremenmorewomenarejoining.439ForexamplesmokejumpersemployedintheU.S.mustbe120to200pounds54to91kilogramssotheydon'tgetblownawaybythestrongwindsorgethurtwhentheyland. Smokejumpersmustalsobecapableofsurvivinginthewilderness.InRussiamanysmokejumpersknowhowtofindfoodintheforestandevenmakesimplefurniturefromtrees.5Butforthesefirefighterssmokejumpingisn'tjustajob.Theylovebeingabletojumpoutofplanesfightfiresandliveintheforest.As28﹣year﹣oldRussiansmokejumperAlexiTishinsaysThisisthebestjobfortoughguys. A.Whatisasmokejumper? B.Howdosmokejumpersdoit? C.Moreimportantareyourheightandweight. D.Itmeanstheworkisdangerousandtakesalongtime. E.Andhomesaredamagedandthousandsofpeopledie. F.Theycarrywaterwiththemtoobutonlyalimitedamount. G.Hotweatherandfast﹣movingwindsoftenmakethesefiresmoredangerous.
Chinaishometodifferentkindsofsoybeans.In2011thesoybeanoutputofChinadropped1thefourthplacearoundtheglobe2accountforonly5.55%oftheworld'stotal.Chinanowrelies3muchonimporttomeetadomestic国内的needfortheplantthanever. ActuallyGaiJuyiisoneofthemillionsofdiligentChinesepeople4workhardtochangethesituation.Forovertwo5decadeGaiandhisteamwentintovariousfieldsacrossthecountryjusttocollectseedfromthefarmers.Noneoftheseedsisthesame.hesaid.Seedcollectionisalreadynoeasyjob.Andtheyeven6havetodelaytheprocessfromtimetotimebecauseofalackoffundingmanyofGai'sstudentsleft7industryforthesmallfinancialpayback.8Gaihasremainedinhispostandsparednoeffortsinlookingafterthepreciousseeds. ThehardworkofGaiandhisteam9finalpaidoff.ThankstothemChina'ssoybeanharvestdoubledovertheyears.TheoldmansaidIknow10mypersistencemeanswhenIseeself﹣producedtofuandsoybeanmilkonChinesepeople'stable.
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下列图形中是中心对称图形的是
若关于x的分式方程+＝3的解为正实数则实数m的取值范围是．
假定你是李华你校将举办诵经典;学汉语ReadClassicsandLearnChinese活动你的英国朋友John对此很感兴趣发邮件向你询问有关情况请根据以下要点用英语给他回复. 1.活动时间及地点;2.诵读内容及形式;3.邀请他参加. 注意: 1.词数100左右;2.可以适当增加细节以使行文连贯; 3.开头和结尾已为你写好不计入总词数. HiJohn Yours LiHua
Canyouimaginedigginginyouryardonedayandfindingalife﹣sizedsoldiermadecompletelyofclay?That'swhathappenedseveraldecadesagowhenfarmersinXi'anChinawerediggingwells. Archaeologists考古学家havesincefoundabout6000moreofthesesoldiersalongwithhorsesweaponstoolsandotherartifacts.ThehugearmywasmeanttoprotectthetombofthefirstrulerofChina.ThefirstemperorofChinaQinShihuangaccomplishedahugeamountduringhisrule.Between221and210B.C.hestartedtheconstructionoftheGreatWall.Hebuiltalargenetworkofroads.Heintroducedanewwritingsystemcurrency货币andasetofmeasurements.Theemperoralsoorderedtheconstructionofahugearmyoflife﹣sizedterracottasoldiers.Thesehehopedwouldprotecthistombafterhisdeath. ThesoldiersinXi'an'sterracottamuseumaretodaylightbrownbuttheyweren'talways.Theybeganasanarmyofredblueyellowgreenwhiteandpurple.Sadlymostofthecolorsdidnotlasttothepresentday.Afterbeingexposedtoairduringexcavation挖掘thecoatingunderthepaintbegantofalloff.Thepaintdisappearedinlesstimethanittakestoboilaneggtakingwithitimportantpiecesofhistory. Nownewtechniquesarestartingtorevealthearmy'struecolors.Archaeologistshaverecentlydiscoveredanareawithmorethanahundredsoldiers.Manyofthesestillhavetheirpaintedfeaturesincludingblackhairpinkfacesandblackorbrowneyes.ChineseandGermanresearchershavedevelopedaspecialliquidtohelppreservethesoldiers'colors.Aftertheyfindasoldierorotherartifacts手工艺品archaeologistssprayitwiththeliquid.Theythencoveritinplastic.Archaeologistsarealsofindingcolorsinthedirtaroundthesoldiers.It'simportantnottodisturbthedirtsothecolorswon'tbelost.WearetreatingtheearthasanartifactsaysarcheologistRongBothemuseum'sleadingchemist.ThenextchallengesaysRongistofindawaytoapplythecolorstothearmyagain.OncethathappensartistscanbringEmperorQin'sarmybacktolifeinfullvividcolor. 1Theterracottasoldierswereconstructedto. A.showtheoutsideworldaboutChina'sgreatness B.beenjoyedbyeverydaypeople C.frightenChina'senemies D.protectEmperorQin'stomb 2Whatisthemainideaofthethirdparagraph? A.Thesoldierslosttheircolorsveryquickly. B.Thesoldiers'paintfelloffbecauseofthehightemperature. C.Visitorstothemuseumarenotactuallyseeingtherealsoldiers. D.Beingexposedtowaterisbadforthesoldiers. 3Whathavearchaeologistsrecentlydiscovered? A.Aplacewithoverahundredsoldiers. B.Awrittendescriptionofthesoldiers'truecolors. C.Aspecialliquidinthetombtopreservethesoldiers'colors. D.AnewtombforEmperorQin. 4WhichstatementwouldRongBoprobablyagreewith? A.Thesoldiersshouldstayintheircurrentbrowncolor. B.Artistsshouldbeabletopaintthesoldiersinanycolortheywant. C.Archaeologistscanonlyguessatthesoldiers'originalcolors. D.Weshouldtrytorestorethearmy'svividcolors.
OnthemorningofJuly141960JaneGoodallarrivedontheeastshoreofLakeTanganyikaandtheGombeNationalPark.Thenaround5pmsomebodyreportedthattheyhadseenachimpanzee黑猩猩.StraightawayJanesetoffintotheforesttofindherchimpanzees. AsayoungwomanJaneGoodallhadnoscientificknowledgebutthisdidn'tstopherfromfollowingherchildhooddreamofstudyingchimpanzeesinAfrica.Aftermanymonthsofdifficultworkshefound:chimpanzeeseatmeattheyusetoolstogetfoodandtheyalsomaketools.EveryeveningJanewroteherfindingsinadiaryandshebegantopublisharticlesinjournals.AfterawhilescientistsstartedreadingherstudiesandJanewasofferedaplaceatauniversity.AftermoreyearsofresearchshebecameDoctorJaneGoodallin1966.TherewasafilmMissGoodallandtheWildChimpanzees1963andthenthefirstofmanybookscalledMyFriendstheWildChimpanzees1969. Duringthe1970sGombebecameadangerousplacetoworkwhereoftentherewasfightingbetweensoldiers.ManyforeignersfledtheregionbutJanestayed.AdifferentproblemdevelopedinGombeinthe1980s.Thehumanpopulationintheregionwasincreasing.AsaresultofthistherewereonlyaboutahundredchimpanzeeslivinginGombe.Janerealisedthatsomethinghadtobedonesoshesetabouthelpingthelocalcommunitytogrowmoretreesforthemintheregion. After1989Janestartedgivinglecturesfightingagainstthecrueltytochimpanzeesusedinmedicalresearchlaboratories.Shewasalsobusysettingupsanctuariesforchimpswhichhadbeencaughtorwereorphans孤儿becauseofthetradeinchimpanzeemeat.NowadaysshehasverylittlesparetimeleftbutshestillspendspartofeveryyearintheforestinGombewatchingherchimpanzees. 1InwhichorderdidJanedothefollowingthings? a.receivedherdoctor'sdegree b.madediscoveriesaboutchimpanzees c.wroteherfirstbookaboutchimpanzees d.gavelecturesaboutchimpanzeeprotection A.bacd. B.adbc. C.acdb. D.abdc. 2WhatwastheproblemthathappenedtochimpanzeesinGombeinthe1980s? A.Diseasesmadetheirpopulationdropsharply. B.ManyforeignerstookthemawayfromGombe. C.Theirhomeswerealmostdestroyedbyhumans. D.Fightingamongsoldiersbrokeoutintheirhomes. 3Whichofthefollowingbestexplainssanctuariesunderlinedinthelastparagraph? A.Modernhospitals. B.Safehouses. C.Wildlifemarkets. D.Researchlabs. 4WhydoestheauthoruseherchimpanzeesinParagraph1and4? A.TotellusJaneistheirprotectionhero. B.ToproveJane'sresearchneedsthem. C.ToexplainJanehasraisedthem. D.ToshowJanelovesthemdeeply.
ThestudyonfacialrecognitiontechnologyFRTbeganinthelate1960s.Inthelate1990sFRTbegantoenterthemarketgraduallybutitsaccuracyhadalongwaytogothoughitcostgovernmentsalotwhichmadeitunpopularatthattime.FRTattractedwideattentionafterSeptember112001andithasbeenwidelyusednow. RecognizingthepotentialabuseintheuseofFRTMicrosoftisaskingtheU.S.governmenttostudyfacialrecognitionFRandkeepadosewatchoveritsuse.PersonallyIholdthisisapositivejobthatMicrosoftisdoing.FRThasgrowntobesopowerful.Itcanbeusedtoidentifypeopleinphotosvideofeedsandofcourseinpersonwithouttheirpermission. Mr.BradfordSmithMicrosoft'spresidentsuggeststhatgovernmentsaroundtheworldshouldexaminecommercialusesofFR.TheEuropeanUnionEUisaheadofothersinthisaspectthankstoitstoughnewdataprotectionlawwhichforbidscompaniestogatherthebiometric生物特征dataneededforfacialrecognitionwithoutfirstobtaininguserspermission. SanFranciscohasbecomethefirstcityintheUSAtoforbidusingfacialrecognitionsoftware.AndOaklanddiscussedasimilarrulelastmonth.SanFranciscohassaidthatpoliceandotherpublicdepartmentscannotuseFRT.SanFranciscoalreadyusessurveillance监视camerasforreadingcarnumberplatesandpoliceofficerswearbodycameras.SanFranciscoofficialAaronPeskinsaidFRTwaslikeBigBrotherfromthebook1984byGeorgeOrwell.ThephraseBigBrotherisnowusedtodescribeattemptstoincreasesurveillanceandspyoncitizens.Mr.PeskinsaidWecanhavegoodpolicingwithoutbeingapolicestate. 1WhywasFRTunpopularinthe1990s? A.Itwasinconvenienttouse. B.Itwasexpensivetoproduce. C.Itsaccuracyneededimproving. D.Itsrolesweren'tfullyfoundout. 2Whatistheauthor'sattitudetoMicrosoft'sadviceonthemanagementofFRT? A.Hesaysyestoit. B.Heisdoubtfulofit. C.Hefeelsworriedaboutit. D.Hecan'tunderstandit. 3WhohasdonethemostworktomakepeopleuseFRTinarightway? A.SanFrancisco. B.Microsoft. C.Oakland. D.TheEU. 4Whatwouldbethebesttitleforthetext? A.BigBrotherTechnology B.DifferentUsesofFRT C.StrongProtectionofFRT D.FRData'sDisadvantages
如图在平面直角坐标系中已知点A﹣36B﹣9﹣3以原点O为位似中心相似比为把△ABO缩小则点A的对应点A′的坐标是
如图所示将形状大小完全相同的“●”和线段按照一定规律摆成下列图形第1幅图形中“●”的个数为a1第2幅图形中“●”的个数为a2第3幅图形中“●”的个数为a3…以此类推则+++…+的值为
MyhusbandandIonlyhaveonecar.SoafterworkIalwayswalktohisofficeandwaitforhimto1mehome. OnedaywhileIwaswaitingforhimabeautifulcar2nearme.IwasbusilyadmiringthecarwhenI3thedriver.Honestlyshewasprobablythe4womanIhadeverseenoutsideofamoviescreen.Her5wereasblueasseaandshehadteethlikeanevenrowofpearls.Minuteslateramancameoutofthebuildingandwalkedovertoher.Theykissedanddroveoff. Sittingthere6injeansandaT﹣shirtIwantedtocry.Itisso7thatpeoplehaveitall. ThenextweekIsawheragainandafterthatitbecamealmost8toseeher.Iwould9ifsheandherhusbandateoutalotandwheretheywent.Iwantedherto10thecarsoIcouldseeherinfulllength.Didshe11classyhigh﹣heeledshoes? Afewweekslaterthisquestionwas12forme. Iwaswaitinginmyusualplaceandthewoman'shusbandcameovertotheircar.Heopenedthedoor.13theprettywomanwalkedaroundtothepassengerside14onawalkingstick.She15onelegwithherhandsandthentheotherone;shehadaprosthetic假肢onherleftlegandabrace支架herrightone. AstheydroveawayIbegantocry.WhenmyhusbandarrivedItoldhimwhathad16.Hesaidheknewherhusbandandthatwhentheladywas12yearsoldshehadbeen17inacarthatgotstuckontherailroadtracks.Bothherparentswerekilled.Therailcompanymadealargesettlementwithherbecausethecrossinghadno18;thatiswhysheownedsuchanicecar. ForweeksIhad19thiswomanandherwayoflife.NowIrealizehowluckyIam.Whenyoumeetapersonwhoseemstobemuchbetteroffthanyoudon'tbefooledby20. 1A.walk B.drive C.fly D.ship 2A.rangup B.spedup C.wentup D.pulledup 3A.noticed B.recognized C.greeted D.observed 4A.prettiest B.proudest C.strictest D.strongest 5A.fingers B.ears C.eyes D.nose 6A.covered B.wrapped C.put D.dressed 7A.touching B.unfair C.interesting D.surprising 8A.boring B.stressful C.routine D.amusing 9A.refer B.whisper C.wonder D.expect 10A.getoutof B.getinto C.goup D.gothrough 11A.wear B.oppose C.abuse D.ban 12A.raised B.handled C.solved D.answered 13A.Immediately B.Slowly C.Curiously D.Fortunately 14A.putting B.carrying C.turning D.leaning 15A.pressed B.skipped C.lifted D.slid 16A.disappeared B.changed C.happened D.lost 17A.limited B.trapped C.lost D.sunk 18A.announcement B.signals C.appeal D.station 19A.envied B.ignored C.respected D.understood 20A.confidence B.confusion C.ambition D.appearance
NewYorkCitymuseumshavefilled2019withexcitingexhibitions.Herearehighlightsasyouschedulethatleisuretime: TheStatueofLibertyMuseum LibertyIsland StartingMay16 AbrandnewmuseumabouttheStatueofLibertyisopeningonLibertyIslandwiththreeroomswithinthespaceincludinga3Dimmersive拟真的theaterthatwillplayan8﹣to﹣10﹣minutefilmthattellsabriefhistoryofitsbeginningsanditsmeanings. 'CyclingintheCity' MuseumoftheCityofNewYork JulythroughDecember TheMuseumoftheCityofNewYorkisopeninganewexhibitaboutthehistoryofcyclingandthecity'srelationshipwithitcalledCyclingintheCity:A200﹣YearHistorythrough50objectsincluding14bicyclesphotographsandcyclingclothing.TheexhibitionwillalsofeatureancientandmodernfilmsshownonalargescreenwhichwillenablevisitorstoexperiencevirtualcyclinglandscapesviaZwiftanonlinecyclingvideogame. 'ShePersists:ACenturyofWomenArtistsinNewYorkCity' GracieMansion StartingJuly14 With60worksbymorethan40artistsGracieMansioniscelebratingtheexcellentworksofwomenwhocalledNewYorkhomeinthisnewexhibit.Thepaintingsfilmphotographycraftanddesignaredividedintothreethemes:bodyasabattlegroundpicturingpeopleandexpandingabstraction. MuseumoftheDog 101ParkAve. StartingOct.6 Anentireartmuseumaboutdogshasarrivedin Manhattanwithalargetwo﹣floorcollectionofpaintingssculpturesandrarepiecesfromfamousdogartists.ThereareinteractiveexhibitslikeaFindYourMatchandaMeettheBreedstouchscreenwhereyoucanexploredifferentbreeds'featurestraitsandhistories. 1Atwhichplacecanpeoplelearnthehistoryofcycling? A.LibertyIsland B.MuseumoftheCityofNewYork C.GracieMansion D.101ParkAve. 2WhichofthefollowingisNOTopenduringthesummercamp? A.TheStatueofLibertyMuseum B.'CyclingintheCity' C.'ShePersists:ACenturyofWomenArtistsinNewYorkCity' D.MuseumoftheDog 3Whichofthefollowingisatraditionalexhibitionwithoutusingdigitaltechnology? A.TheStatueofLibertyMuseum B.'CyclingintheCity' C.'ShePersists:ACenturyofWomenArtistsinNewYorkCity' D.MuseumoftheDog
Imagineyouareopeningyourowncompanyandwanttohireamanager.Youhavetwoapplicantsandtheyarebothskilledandexperiencedsowhowouldyouratherhire:JuliaWatsonorShobhaBhattacharya?ChancesarcthatyouwouldpreferWalsonright?Butwhy? EasynamesareregardedasmorefamiliarlessriskyandlessdangerousErynNewmanascientistatVictoriaUniversityofWellingtonNewZealandtoldScientificAmerican.Asaresultpeoplewitheasiernamesareoftenconsideredtobemoretrustworthy. ThisiswhatNewmanandherteammateshavefoundintheirrecentstudy.Intheexperimenttheypicked218differentforeignnamesincludingdifficult﹣to﹣pronounceoneslikeYevgeniDherzhinskyandeasynameslikeBodoWallmeyer.Theythenattachedeachnamewithastatementsuchasturtlesaredeafandgiraffesaretheonlymammalsthatcannotjumpandaskedvolunteerswhethertheythoughtthestatementsweretrue.Theresultsshowedthatstatementsconnectedtoeasiernamesweremoreoftenrankedasbelievablethanthosebelongingtodifficultnamesregardlessofwhatthetruthreallywas. Infactpreviousstudieshavealreadyfoundthatourjudgmentsaboutproductscanbeaffectedbytheirnames.Forexamplewetendtothinkofafoodadditivewithaneasiernameassaferandastock股票withaneasiernameasmoreprofitable赢利的accordingtoMedicalDaily.Butresearcherspointedoutthatthiseffectcanchangedependingonwheresomeonecomesfrom.ForexampleanativeBritishmanmayfindYevgeniDherzhinskyhardtopronouncewhileRussianpeoplecansayitwithouteffort. Newmanhopesthatthisfindingcanmakeusbetterseeourbias.It'snotjustunfairtopeoplethatwemakejudgmentsbasedonfeelingsratherthanfacts﹣itcansometimeshaveseriousresults.Forexamplewemaychoosetobelievecertaineyewitnessesincourtsimplybecausetheirnamessoundmoretrustworthyeveniftheyareactuallylying.Orwemayletgoofqualifiedjobapplicantsduetotheirdifficultnames. NowifyoucouldmakethatdecisionagainwouldyoustillpreferJuliaWatsontoShobhaBhattacharya? 1WhydoestheauthorrefertothechoicebetweenthetwonamesinParagraph1? A.Tointroducehowtochooseagoodapplicant. B.Toshoweasynamesareconsideredmorerisky. C.Toexplainwhatkindsofapplicantsareconsideredreliable. D.Tomakereaderswonderwhyapplicantswitheasynamesarepreferred. 2WhatdidNewmanandherteammatesdiscoverintheirexperiment? A.Hard﹣to﹣pronouncenamesdidn'tinfluencehowthevolunteersjudged. B.Statementspairedwitheasynameswereratedasreliableinmanycases. C.Volunteerswitheasiernamesweremorelikelytochoosetruestatements. D.Statementsconnectedwithdifficultnamesweremoretrustedbyvolunteers. 3TheunderlinedwordbiasinParagraph5probablymeans A.realfact B.wisejudgment C.goodunderstanding D.unreasonablepreference 4Whatcanbeconcludedfromthepassage? A.Weshouldthinktwicebeforewemakeadecision. B.Russianshavemorefairnesstopeople'snamesthantheBritish. C.Judgingpeoplebasedontheirnamesmaycauseseriousproblems. D.Theharderyournameispronouncedthemorelikelyyouwillgetajob.
下列运算正确的是
Manyscientistsbelieveourloveofsugarmayactuallybeanaddiction瘾.Whenweeatordrinksugaryfoodsthesugarentersourbloodandaffectspartsofourbrainwhichmakesusfeelgood.Thenthegoodfeelinggoesawayleavinguswantingmore.1Inthiswayitisinfactanaddictivedrugonethatdoctorssuggestweallcutdownon. ItseemslikeeverytimeIstudyanillnessandsearchforthefirstcauseIfindmywaybacktosugarsaysscientistRichardJohnson2Why?SugarwebelieveisoneofcausesoftheproblemifnotthemajorreasonsaysJohnson. Ourbodiesaredesignedtosurviveonverylittlesugar.Earlyhumansoftenhadverylittlefoodsoourbodieslearnedtobeveryefficientinstoringsugarasfat.Inthiswaywehadenergystoredforwhentherewasnofood.Buttodaymostpeoplehavemorethanenough.3Wellwhatisthesolution?It'sobviousthatweneedtoeatlesssugar.4Frombreakfastcereals谷物toafter﹣dinnerdessertsourfoodsareincreasinglyfilledwithit. 5Manyschoolsarereplacingsugarydessertswithhealthierfoodlikefruit.Otherschoolsarcgrowingtheirownfoodingardensorbuildingfacilities设施likewalkingtrackssostudentsandothersinthecommunitycanexercise. A.Buttherearethosewhoarefightingbackagainstsugar. B.High﹣sugarfoodscannegativelyaffectyourenergylevels. C.Sotheverythingthatoncesavedusmaynowbekillingus. D.Alltastyfoodsdothisbutsugarhasaparticularlystrongeffect. E.Thetroubleisintoday'sworldit'sextremelydifficulttoavoid. F.Theaveragepersontakesinabout24kilogramsofsugareachyear. G.1/3ofadultsworldwidehavehighbloodpressureand2.5billionsufferfromobesity.
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∧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. Ourschoolhasalonghistory.Itissuchbeautiful.ButrecentlyIoftenfindsomestudentsdosomethingbadtoourschool.ForanexamplelastFridayIsawastudentspittinginthecorneroftheschoollibrary.Itellhimnottodothatbuthedidn'trespondtomeandwentstraightawaywhatmademesad.There'snodoubtthatitisourdutykeepourschoolcleanandtidy.Weshouldn'tleaverubbisheshereandthere.Drawpicturesinthewalliscertainlyabadhabit.IfeveryoneofuscontributemoretoourschoolImsureshewillbecomemoreandmorebeautifully.
OnthenightofAugust242001everythingchangedwhenmyfriendscarhitawallwithmeinside.IlostmostofmyrightlegandIwasleftbleedingwithseveralbrokenbones.Atthehospitalalthoughmybodywasweakmymindwasstillveryclear.Ijustkepttellingmyselftoholdon.AweeklaterImadeadealwiththedoctorsthatonceIcouldrollontomysideIcouldleave. TwoweekslaterIwasallowedtogohome.AlthoughIleftthehospitalthefightwasfarfromover.Myleftkneewasbadlyinjuredwhichresultedindifferentsurgeries手术overthenextfewyears.AndsoonmoreofmyrightleghadtoberemovedThismadeithardertowearmyfalselegsoIdonatedittoanursewhocouldn'taffordoneforherself.ThejoyofbeingabletoprovidethisgifttosomeoneelsewasgreaterthanthehappinessIfeltonanydayIwasabletowearitmyself. Peopleoftentellmethey'reproudofmeforstayingstrong.Butinmymindstayingstronghasalwaysbeenmyonlychoice.SoonthedayIleftthehospitalImadeapromisetomyselftoalwayslivelifetothefullest. NowImaynotbeabletodothingsthewayeverybodyelsedoesthembutstillIalwaysfindawaytodothem.IsoonsettledintoeverydaylifeagainuntilonedayIrealizedIwasn'tlivingmylifeasfullyasIwantedto. After13yearsofthinkingthatIwasconfidentIhadanunfamiliarfeelingsweepoverme.ForthefirsttimeinmylifeIwasnotonlyconfidentbutIwantedtohelpthosearoundme.In2014Ievenstartedmodeling.MydreamisthatonedayalittlegirlwillseemeinamagazineandsayWowshe'sbeautifulandsheonlyhasoneleg.IcoulddothattoosomedayeventhoughIhaveadisability. 1Howdidtheauthorfeelafterthecaraccident? A.Shefeltluckythatshewasstillalive. B.Shetookapositiveattitudetowardlife. C.Shecouldn'tacceptthelossofherleg. D.Shecomplainedthatlifewasunfairtoher. 2Whatmadetheauthorfeelhappyaccordingtothetext? A.Shecouldwearherfalselegagain. B.Shehadlivedherlifetothefullest. C.Shewasabletoofferhelptoothers. D.Shecoulddothingslikeeverybodyelse. 3Whydidtheauthorstartmodelingin2014? A.Toappearonthecoverofamagazine. B.Toprovedisabledpeoplecouldalsosucceed. C.Tochallengeherselfbytryingsomethingnew. D.Toencourageotherstobeconfidentofthemselves. 4Whatwastheauthor'smainpurposeinwritingthetext? A.Tostresstheimportanceofhavingadream B.Toshowhowdifficultlifeisfordisabledpeople. C.Togiveadvicetodisabledpeopleonhowtomakealiving. D.Toshareherpastexperiencesandhowshediscoveredherdream.
为庆祝新中国成立七十周年你们学校即将举办一次大型文艺汇演GrandArtandCulturalShow.假如你是李华请给你们学校留学生Eric写一封邮件邀请他参加观看. 内容包括: 1.汇演时间和地点; 2.汇演内容和意义. 注意: 1.词数:100左右. 2.可以适当增加细节以使行文连贯.
Theinternetisn'talwaysahappyplace.Buttherearegroupstryingtochangethat.KuakuaqunorpraisinggrouponWechatinwhichpeoplesendoutcomplimentsandpositivemessagesarebecomingpopularamonguniversitystudentsinChina. PraisinggroupshavebeenfoundedbystudentsfromseveraluniversitiessuchasFudanUniversityCommunicationUniversityofChinaHuazhongUniversityofScienceandTechnology.PeoplecanevenbuymembershipsofsuchgroupsononlineplatformslikeTaobao.Onceadmittedtheymakecomplimentarycommentsabouteachotherandevenasktobecomplimentedonparticularthings. ThepraisinggroupscomeatatimewhenthementalhealthofyoungChineseisgettingattention.AsyoungChineseseekcompanyandconfidencethepraisinggroupsmeetalotofpsychologicalneeds.ThegroupallowsmetoseethegoodqualitiesinmyselfthatIoftenoverlookandlookatthebrightsideofeverything.KindnessfromstrangerscanhelpmefeelmuchbetterTianJiayin22toldChinaDaily. ThepopularityofchatgroupsisalsoareflectionofChineseculturereportedGlobalTimes.AsmanyyoungChineseareraisedtobemodestit'suncommonforthemtoopenlyseekandgivepraise.Asaresulttheydesirecomplimentsastheygrowup.Ifthekidsgotmorepraisefromparentsandteacherstheirdesireforpraisewouldn'tbesostrongsaidDaiJiapsychologistfromHunanUniversityofCommerce. ButChenKanapsychologistfromFudanUniversitywarnedthatmembersofpraisinggroupsshouldbecautiousaboutgivingorreceivingpraise.Thebiggestriskistheconstantemphasisonthe‘falseself'whichmakesithardertoseethe‘trueself'shesaid. 1WhatdoestheunderlinedwordcomplimentsinParagraph1mean? A.praises B.questions C.advice D.information 2WhydomanyChineseuniversitystudentslikeKuakuaqun? A.ItgivesthemadiscountonTaobao. B.Ithelpsthemwiththeirstudies. C.Itmakesthemfeelconfident. D.Ithelpsthemmakenewfriends. 3WhatdoesChenKanthinkofgivingorreceivingpraise? A.Receivingpraiseismorehelpfulthanbeingmodest. B.Parentsandteachersshouldgiveyoungpeoplemorepraise. C.kidsshouldbeencouragedtoopenlyseekandgivepraise. D.Toomuchpraisemightstopkidsfromseeingtheirtrueselves. 4Whatisthemainideaofthearticle? A.Tipsforgettingmotivated B.ThelostgenerationinChina C.OriginofthepraisingcultureinChina D.AdvantagesanddisadvantagesofKuakuaqun
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