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已知椭圆C：（a＞b＞0）的实轴长为4，焦距为2． （1）求椭圆C的标准方程； （2）设直线经过点P（2，﹣1）且与椭圆C交于不同的两点M，N（异于椭圆的左顶点）设点Q是x轴上的一个动点，直线Q...
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高二下学期数学《》真题及答案
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已知椭圆C.＋＝1a>b>0F.0为其右焦点过F.且垂直于x轴的直线与椭圆相交所得的弦长为2.则椭圆
已知椭圆长轴在轴上.若焦距为则等于
4
5
7
8
根据下列条件求椭圆的标准方程1两准线间的距离为焦距为22已知P.点在以坐标轴为对称轴的椭圆上点P.到
设A.B.分别为椭圆＝1a>b>0的左右顶点椭圆长半轴的长等于焦距且直线x＝4是它的右准线.1求椭圆
已知椭圆的中心为坐标原点O.椭圆短半轴长为1动点M2tt>0在直线x＝a为长半轴c为半焦距上.1求椭
对于椭圆下面说法正确的是
长轴长为2
短轴长为3
离心率为
焦距为1
已知椭圆的长轴长与焦距比为21左焦点F.-20一定点为P-80.I求椭圆E.的标准方程Ⅱ过P.的直线
1已知椭圆的焦点在x轴上长轴长为4焦距为2求椭圆的标准方程2已知双曲线的渐近线方程为y=±x准线方程
已知双曲线的实轴长虚轴长焦距长成等差数列则双曲线的离心率e为
2
3
已知椭圆＝1长轴在y轴上.若焦距为4则m等于
4
5
7
8
已知椭圆C的中心在原点焦点在x轴焦距为2且长轴长是短轴长的倍．椭圆C的标准方程为．
已知直线相交于A.B.两点1若椭圆的离心率为焦距为2求椭圆的标准方程2若其中O.为坐标原点当椭圆的离
已知焦点在y轴上对称轴为坐标轴的椭圆半短轴长为3焦距为4则该椭圆的标准方程为
已知椭圆＝1长轴在y轴上.若焦距为4则m等于.
4
5
7
8
已知椭圆长轴在y轴上若焦距为4则m等于
4
5
7
8
已知离心率为的椭圆的中心在原点焦点在x轴上.双曲线以椭圆的长轴为实轴短轴为虚轴且焦距为2.求椭圆及双
已知椭圆C.的两焦点分别为长轴长为6⑴求椭圆C.的标准方程;⑵已知过点02且斜率为1的直线交椭圆C.
已知椭圆的中心为坐标原点O.椭圆短半轴长为1动点M.2tt＞0在直线x=a为长半轴c为半焦距上.1求
已知椭圆长轴在y轴上若焦距为4则m等于
4
5
7
8
已知直线相交于A.B.两点.若椭圆的离心率为焦距为2求线段AB的长2若向量互相垂直其中O.为坐标原点
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I'daitifyoucouldgivemesomevaluableadviceonhowtolearnEnglishwell.
Anyexerciseisgoodexercisebutwhenitcomestolosingweightit'shardtobeatrunning.Afterallrunningisoneofthemostefficientwaystoburncaloriesandgetfitwithouthavingtorestrictyourdiet.1Ifyou'renotarunneryetbutinterestedinlosingweightherearefourreasonsrunningcanbethebestexerciseforweightloss. 2Whencomparingrunningwithwalkingthesamedistancestudiesfindthatrunningwillleadtogreaterweightlossmostlikelybecauseyourrestingenergyexpenditurestayselevated高的afteryourun.Inalong﹣termcomparisonstudyofrunnersandwalkerscaloriesburnedthroughrunningledto90%moreweightlossthancaloriesburnedthroughwalking. Runningistime﹣efficient.Evenifthemyththatrunningamileandwalkingamileburnthesamenumberofcaloriesweretruerunningisaconsiderablyfasterwaytoburnthosecalories.3 Runningisconvenient.Thoughmanyofushaveaccumulatedavastarsenal武器装备ofGPSgadgetsandtechteesovertheyearslittleisactuallyrequiredtogorunning.Youcandoitalone.Youcandoitalmostanywhere.4Forthisreasonalonerunningisthebestworkoutforweightlossbecauseit'scheapandaccessibleandtherearefewerbarrierstomaintainingaroutineevenwhiletraveling. Twowordsrunner'shigh.5Fortunatelystudiessupportwhatmanyrunnershaveexperiencedonananecdotallevel﹣runningcanactuallygetyouhigh.Scientistshavefoundlinksbetweenmoderatetointenseexerciseandmorphine﹣likebrainchemicalswhichexplainstheoccasionalfloodofthrillthatrushesoveryouduringahardrun.Thathappysensationyouhadafteryourlastracemakesyouwanttogoforanotherrunright? A.Cultivatethegoodhabitofrunning. B.Runningworksevenwhenyou'reatrest. C.Youwillneversticktoahabitifyoudon'tlikeit. D.Thefirstruleofexercisingforweightlossisthatifyoudon'tenjoyityouwon'tstickwithit. E.Youdon'tneedanyequipmentbeyondapairofrunningshoes. F.Ifyou'realreadyarunnerkeepon. G.Mostpeoplecanruntwoorthreetimesasfarastheycanwalkinagivenamountoftime.
假定你是李华你的外教老师Jack对中国传统文化很感兴趣想了解即将到来的中国的中秋节.请你写信向他介绍这个节日.内容包括 1.收到邮件的心情 2.简单介绍该节日 3.邀请他一起过节. 注意 1.词数80左右 2.可适当增加细节以使行文连贯.
Billisagpersonwhohasgivenmillionsofdollarstohelpthosepeopleinthedisaster﹣hitarea.
Placestoavoidtravelling IndiaThebigdifferenceinwealthandclassmayleadtosomeoftheriskofcrimesinthiscountry.ButaccordingtoJohnGobbelsachiefofficerforMEDJETaninternationalemergencyorganizationit'smedicalsafetythatactuallymakesIndiasodangerous.HeexplainsthattheU.S.StateDepartmentgivesthecountryLevel2traveladvisorystatusLevel1meansyoushouldexercisenormalprecautions预防措施Level4isdonotgo HawaiiConsideringthisdestinationisaveryhotspotforhoneymoonersitmightbesurprisingtoseetheBigIslandofHawaiiasadangerousplacetovisit.TheeruptionofavolcanohasputKilaueainastateofemergencywithpoisonousgaslavaflowsandearthquakesallarisk.You'lllikelyseespecialairlinedealscancelledsothinktwicebeforemakingthisflight. AcapulcoThisbeachresorttownonMexico'sPacificcoastisn'texactlythewhite﹣sandpartydestinationitoncewas.WithaLevel4traveladvisoryGobbelsexplainsit'sinthesamecategoryasplaceslikeIranSyriaandNorthKoreaIt'sregardedasthemurdercapitalofthecountry. CairoEgyptAccordingtoarecentreportfromtheThomsonReutersFoundationCairoisconsideredthemostunsafecityforwomenintheworld.EventhoughthepoliticaltensionsareeasinginthisareaaccordingtoGobbelssexualviolenceandculturalexpectationsmakeitextremelyproblematicforbothlocalsandvisitors. 1AccordingtoJohnGobbelswhichisdangerouswhiletravellinginIndia? A.Personalbelongings B.Travelinsurance. C.Medicalsafety. D.Culturaldifference. 2Whichplacementionedaboveisespeciallydangerousforawomantourist? A.Cairo. B.India. C.Acapulco. D.Hawaii 3Whatcanbeinferredfromthetext? A.ALevel3traveladvisoryindicatesyoucangowithnormalprecautions B.Syriaisn'tariskydestinationwhereyou'llhaveawonderfulvacation. C.TheflightstoHawaiimaybechangeableduetotheeruptionofthevolcano D.ThepoliticaldisorderinCairoisresponsibleforitsunsafetyatpresent.
When1learntodrivewearetoldtoobeythetrafficrulesandnottodriveourvehiclestoofast.2surprisesusisthatsomeyoungpeoplejustenjoythefeelingofdrivingcarsormotorcyclesataveryhighspeed.Jack318﹣year﹣oldboyis4exception. RecentlyJack'sfatherhasboughthimacar5isquiteadmiredbyhisfriends.Whenheisoutinthecountrywherethereareafewpeopledrivingandthetrafficrulesarenotstrictthis6adventureboywilldrive7extremefast.IntownshoweverthereisaspeedlimitthatisfiftykilometersanhourbutJackoftendrivesmuchfaster. OnedayJackwasdrivingthroughtownswhenayoungpolicemanwhowasnewtohiswork8stophimandsaidI'mafraidyouweredrivingatamorethanfiftykilometersanhourSir.Pleasegivemeyournameandaddress.9lookatthepolicemancarefullyJacksaidtohimWellsirIstartedmyjourneylessthananhourago.Onhearingthishedidn'tknowtheanswer10Jack'sexcuse.HethoughtforafewsecondsandthenletJackgo.
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2018年7月12日我国科学家姜雪峰教授被评为”全球青年化学家元素周期表硫元素代言人”其是目前为止第一位人选的中国学者．下列说法或推测正确的是
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China'sTeaVillages InmostChineseteavillagesMarchisthetimeofyear1localsstarttopickandprocesstea.Theusuallyquietvillagessuddenlybecomebusycentersofactivityaspeopletakeoutspecialtoolsandprepare2teaprocessing.Insomevillageslocalresidentsholdtraditionalceremonies3thankheavenforitsblessing.Thepriceoftea4pickinMarchisextremelyhighbecause5isfreshtenderandcontainsmultipletraceelements. China6befamousforteaproductionsinceancienttimes.Ofthegoodstransportedandtradedalong7OldSilkRoadlinkingChinatotheMiddleEastandEuropetheimportanceofteawasmatchedonlybysilk.ChinaproducesOolongblackgreenwhiteyellow8darkakapost﹣fermentedtea.TheOolonggreenandblack9varyaremostnotablefortheirhighquality. MostofChina'steavillagesarefoundinremotemountainousareasinthecountry'ssouthandsouthwest10thebeautifulsceneryisoftenhiddenunderclouds.
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随着人们生活水平的提高广场舞大妈们掀起了一场广场舞热潮.针对这一现象不同的人有不同的观点请你以广场舞squaredancing为主题完成一篇文章 内容要点 1优点一种健康的生活方式保持健康和活力结交朋友消除孤独 2问题噪音污染抢占地盘引发争执 3你的看法.
AhospitalhasbeenforcedtobanPokemonGoplayersfromthesiteafteramonsterhub妖怪枢纽站wasfoundintheA&Edepartment.RoyalStokeUniversityHospitaldiscoveredthatitscasualtyunit急诊室isonthesamespotasaPokemonGo‘gym'﹣whereplayerscantraintheirnewlycaughtNintendocreatures. TheUniversityHospitalsofNorthMidlandsTrustagreedlastweekthatpatientscanplayPokemonGoonwardsbecausewalkingaroundishealthy.ButtheTrusthasbeenforcedtopostawarningonitswebsiteaboutpublicaccesstoA&E.ItsaidifPokemonGobecomesamajorannoyanceitwouldaskNintendo﹣whichdecidesonthelocationsofthevirtualgymsaccordingusingGPS﹣tohaveitremovedfromthepremises道馆. KevinParkerassociatechiefnursesaidMembersofthepublicwhodonotneedtobeatRoyalStokeshouldnotattempttoenterA&Eoranyotherpartofthehospitalbuildingtoplaythegame.TheA&Edepartmentisincrediblybusythissummer.Wewantthepublictounderstandthatanybodywhovisitsthehospitalsolelytoplaythegamewillprovideanunwanteddistractiontotheimportantworkofthehospital.I'malsoawareofvariousreportsinthemediaofunsafeareasthatthegamehasbeenplayedin. RoyalStokeUniversityHospitalisasafeareawheregamerscanenjoyPokemonGo.MichelleHarristheTrust'smanagersaidthegamecouldstillbeplayedbythosealreadyinhospital.WerecognisethatthePokemonGogameencourageswalkingandexercisewhichissomethingthattheTrustisequallykeentopromoteshesaid. ThereareanumberofwalkingroutesestablishedthroughouttheTrustthatcanbeusedtocombinewalkingandplayingthegame.Walkingjust30minutesfivetimesaweekcanhelpreducetheriskofpreventableillnessessuchasobesitydiabetesandheartdisease. TherehavebeenseveralwarningsaboutthegamesinceitsUKrelease.LastweekagroupofteenagersinWiltshirewereleftstrandedalmost100ftundergroundaftertheygotcarriedawaysearchingforPokemonGocharacters.Thefourboysaged16and17endedupgettinglostandhadtowaittogetaphonesignalbeforetheycouldcallforhelp.EventuallytheycontactedDorsetandWiltshireFireandRescueteamwhotookthemtosafety.DamienBenceofthefireandrescueteamsaidPokemonGoisobviouslyleadingpeopleintodangeroussituations. 1ItseemsthatPokemonGoisagame. A.designedtohelppatientshaveaquickrecoveryinhospital B.helpingcuresuchdiseasesasobesitydiabetesandheartdisease C.encouragingplayerstowalkandexerciseinsteadofstayingindoors D.warningteenagersoftheplaceseasytogetlostorattacked 2TheA&Edepartmentisincrediblybusybecause. A.morepatients'arrivalincreasestheworkloadoftheA&Edepartment B.doctors'playingthegamemakestheA&Edepartmentlessefficient C.players'injuryincreasestheworkloadoftheA&Edepartment D.players'arrivaldisturbstheworkoftheA&Edepartment 3Theunderlinedwordinthelastparagraphprobablymeans. A.hurt B.disturbed C.trapped D.threatened 4Thepassageismainlyabout. A.thenegativeeffectsofPokemonGosinceitsUKrelease B.theapplicationsofPokemonGoinhospitalssinceitsUKrelease C.thepopularityofPokemonGosinceitsUKrelease D.theestablishmentofPokemonGovirtualgymssinceitsUKrelease
只有在老师进入教室时学生们才停止大声说话. Onlywhentheteacherenteredtheclassroom.
Igrewupwithoutafather.Wellsortof.Myparentsdivorced离婚inthe1960﹩whenIwasasmallchildandIstayedwithmymotherinLosAngeles.MyfatherremarriedandmovedtoasmallsuburbofAtlanta.ForonemonthoutoftheyearinthesummerIwouldflybackandspendtimewithmydadsoIhadafatherattimes. FurtherIhadaseriesofstepfatherswhorangedfromwonderfulguystoalcoholicstodangerousindividuals.HavinglivedthroughsuchexperiencesIfinditamusingwhenpeoplesaythatchildrenreallyneedafatherinthehome.WellifheisagoodfatherandagoodmanthenIagreecompletely.Ifheisnotthenthechildmightactuallybebetteroffwithouthim.Wedon'tjustneedfathers﹣weneedgoodfathers. IfeelitfairtosayIendedupaverysuccessfuladultatleastthat'swhatpeopletellme.SohowdidIdoit?Ithinkitstartedwithmehavingabitofachiponmyshoulder.Normallythisisnotagoodthingbutinmycaseitwasrocketfuelforachievement.Nothavingafatherinmylifegavemesomethingtoproveanditmotivated激励meinanI'llshowyouway. Ialsotriedveryhardevenasalittleboytobeself﹣sufficient.AndthatmeansIdidnotrelyuponmyparentsexcepttotheextentnecessary.ThiskindofindependenceIbelieveishighlymissedinthisageofhighlymanagedchildrenwithhelicopterparentshovering盘旋abovethemconstantly. IalsothinkIneverwantednothavingafatherinmylifetobeanexcuseformyself.WemakeandallowexcusesconstantlythesedaysbutIjustneverfeltthatfeelingsorryformyselfwasgoingtogetmeanywhereIthinkifchildrencanadoptsuchmindsetsearlyintheirlivesitcanbehelpful. 1Accordingtothefirsttwoparagraphstheauthorthinks. A.hisfatherisabadone B.nobodyneedsafather C.childrenneedagoodfather D.childrenreallyneedafather 2Howdidtheauthorendupaverysuccessfuladult? A.Hewasveryintelligent B.Hemadeexcuseforhimself C.Hewasmotivatedbyafather D.Hewasveryindependentandtriedveryhard 3Whatdoestheunderlinedwordself﹣sufficientmeaninparagraph4? A.Abletodependonmyself. B.Abletodressmyselfveryquickly. C.Abletoplaybymyself. D.Abletoworkonmyown. 4Howcanwedescribetheauthorfromthepassage? A.Friendlycleverandwarm﹣hearted. B.Cleverdeterminedandindependent. C.Motivatedhard﹣workingandindependent. D.Motivatedhard﹣workingandwarm﹣hearted.
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科学家发现对冶金硅进行电解精炼提纯可降低高纯硅制备成本．相关电解槽装置如图1所示用Cu﹣Si合金作硅源在950℃下利用三层液熔盐进行电解精炼并利用某CH4燃料电池如图2所示作为电源．下列有关说法不正确的是
NA表示阿伏加德罗常数的值．俗名为“臭碱”的硫化钠广泛应用于治金染料皮革电镀等工业．硫化钠的一种制备方法是Na2SO4+2CNa2S+2CO2↑．下列有关说法正确的是
ItwasalongtimesinceIhadseenmyparentslasttime.LastSaturdayIdrovealongwaytovisitthem1neitherofthemwasathome.SoIwaitedpatientlyattheirhome2theirreturn.Notseeingthemmademereally3. AsIwaswalkingaroundtheirbedroomI4littleremindersofthem.SomeChristmasgiftswerestill5inboxes.Therewere6onthewallwhichIguessmusthavea7meaningtothem.Whattookmybreathawaywasseeingmydad'semblems徽章fromhismilitarysereofourcountry8hewasyoung.Myfathernever9tousabouttheKoreanWars.AsIlookedatthoseemblemshanging10withallthephotosthathetreasuresI11thatthiswasanimportantpartofhislifebutIneverspent12intalkingwithhimaboutthem.Thephotosofmymomwithherclose13mademerealizeherlifebeforeshewasmymom.Ihadbeenso14runningmybusinesstoraisemyownfamilythatI15thechancetoknowabouttheirpastandexperience. Wesometimesdon'trealizesomethingis16forusuntilwehavelostitsoit'snottoolateforustotalktoourparentsabouttheirpast.Iamwritingmystoryto17everyonewhoisfortunatetostillhavetheirparents18toinvestsometimetolearnaboutthem.Iamgratefultohave19ofmyparents.SoIstillhavetimetotalkwiththem.Ihopethatreaderswill20frommystoryandfindthetimetotalkaboutthosethingsintheirlifethatmeansomuchtotheirparents. 1A.and B.or C.but D.so 2A.to B.for C.of D.in 3A.frightened B.embarrassed C.excited D.upset 4A.sought B.saw C.needed D.took 5A.covered B.folded C.hidden D.kept 6A.SantaClaus B.familyphotos C.familytrees D.oldclothes 7A.simple B.special C.past D.real 8A.if B.until C.though D.when 9A.showed B.explained C.talked D.referred 10A.finally B.clearly C.openly D.proudly 11A.realized B.declared C.admitted D.promised 12A.courage B.chance C.time D.energy 13A.students B.teachers C.friends D.children 14A.strict B.eager C.blind D.busy 15A.rejected B.missed C.delayed D.avoided 16A.hopeful B.original C.careful D.important 17A.warn B.demand C.require D.encourage 18A.away B.around C.awake D.alone 19A.both B.neither C.either D.one 20A.make B.change C.benefit D.Recover
OxfordandCambridgehavenowdecidedtoremovethewordsCAN'TandIMPOSSIBLEfromtheirdictionary.JessicaCoxbornin1983inArizonaistheworld'sfirstlicensedarmlesspilot. ThegirlfromTucsonArizonagottheSportPilotcertificatelatelyandbecamethefirstpilotlicensedtoflyusingonlyherfeet.JessicaCoxwasbornwithoutarmsbutthathasonlystoppedherfromdoingonethingusingthewordcan't. CoxgraduatedfromtheUniversityofArizonain2005withabachelor'sdegreeinpsychologyandaminorincommunications.Coxhasnotusedprostheticarmssincesheturned14.Usingherfeetasmostpeopleusetheirhandssheisableamongotherthingstodriveanunmodifiedcarwithanunrestrictedlicensetotypeonakeyboardat25wordsperminuteandtoputinandremovehercontactlenses. JessicaCoxflewinasingleengineairplaneforthefirsttimeviaWrightFlightin2005.Coxearnedherpilot'scertificateonOctober102008afterthreeyearsoftrainingandisqualifiedtoflyalight﹣sportaircrafttoaltitudeof10000feet. She'sagoodpilot.She'srocksolidsaidParrishTraweek42theflyinginstructoratSanManuel'sRayBlairAirport.ParrishTraweekrunsPCAircraftMaintenanceandFlightServicesandhastrainedmanypilotssomeofwhomdidn'tcomeclosetoCox'sabilities. Doctorsneverlearnedwhyshewasbornwithoutarmsbutshefiguredoutearlythatshedidn'twanttouseprostheticdevices.SothenexttimeyouarereadytotellyourselfIcan'tpossibly…rememberthisamazingyoungwomanandchangeyourvocabulary. 1Whatcanwelearnfromthefirstparagraphs? A.OxfordandCambridgefeltalittledisappointed. B.Noarmlesspeoplehadgotapilotcertificatebefore. C.JessicaCoxwasn'tallowedtousethewordcan't. D.Thewordcan'twoulddisappearfromtheEnglishdictionary. 2WhatdoyouthinkofJessicaCox? A.Sheisacleverandbravegirl. B.Sheispositiveanddetermined. C.Sheisindeedapoorlyeducatedgirl. D.Sheonlytakesinterestinaircraft. 3WhatdoestheunderlinedwordprostheticmeaninParagraph3? A.artificial B.damaged C.unusual D.abnormal 4AftergraduatingfromuniversityJessicaCox. A.sufferedfailurewhensearchingforjobs. B.madeastarttotaketrainingtobecomeapilot C.decidedtouseherfeetasmostpeopleusehands. D.triedherbesttotakecareofherselfinherdailylife.
Doyouusuallyfeelyou'reworkinghardbutstillcan'treachyourstudygoals?Herearesomequicktipstohelpyoustudybetter. ♦Studywithapartneroringroups Ratherthanlivinginacavewithyournoseinthebooksalldaygrabafriendfromyourclassandstudywithhim.1 ♦Stepintoyourteacher'sshoes AskyourselfIfIweretheteacherwhatwouldIputonthetest?Youhaveprobablyexperiencedalotofyourteacher'stestsandquizzesbynow.2Teachershavespecifictypesofinformationthattheywantyoutolearn.Thestructureisusuallythesame. ♦Paintpicturesonthepaper Youcanbuildyourknowledgestructureintheformofpictures.It'shardertoremembereachpieceofapuzzleindividuallythanitistorecallthecompletedpicture.3 ♦4 Ahungrybrainisanineffectiveone.Yourbrainneedsthepropernutrientstokeepitgoing.Becauseofthiswhatyoueatanddrinkalsoplaysahugeroleinhowsharpyourbrainis.Healthyfoodsprovidenutrientstoyourbraincellstokeepthemenergized. ♦Takebreakstorelaxyourbrain Yourbrainislikeamuscle.Itcanbealsotiredifyouoverworkit5Ifyoudividestudyinginto15to30minutesblockswithquickbreaksinbetweenyourbrainwillfeelrefreshedgratefulandreadyforthenextchallengeyouthrowat. A.Feedyourbrainfromtimetotime. B.Itneedsexercisetomakeitstronger. C.Relaxyourbrainbyeatinganddrinking. D.You'dbetterlearnfromthemforthenexttest. E.It'snecessarytohavealongholidayandhavenicefood. F.Findwaystoconnectwhatyouarelearningtoreallifeortootherconcepts. G.Groupstudyinghelpsyoutoengageandprocesstheinformationmoredeeply.
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Bytheageoftwoachildwillhaveavofabouttwohundredwords.
AccordingtonewresearchfromtheUniversityofCambridgeinEnglandsheepareabletorecognizehumanfacesfromphotographs. Thefarmanimalswhoaresocialandhavelargebrainswerepreviouslyknowntobeabletorecognizeoneanotheraswellasfamiliarhumans.Howevertheirabilitytorecognizehumanfacesfromphotosaloneisnovel. TherecentstudytheresultsofwhichwerepublishedinthejournalRoyalSocietyOpenScience.ShowthewoollycreaturescouldbetrainedtorecognizestillimagesofhumanfacesincludingthoseofformerPresidentBarackObamaandactressEmmaWatson. Initially最初thesheepweretrainedtoapproachcertainimagesbybeinggivenfoodrewards.Latertheywereabletorecognizetheimageforwhichtheyhadbeenrewarded.Thesheepcouldevenrecognizeimagesoffacesshownatananglethoughtheirabilitytodosodeclinedbyabout15percent﹣thesamerateatwhichahuman'sabilitytoperformthesametaskdeclines. AnyonewhohasspenttimeworkingwithsheepwillknowthattheyareintelligentindividualanimalswhoareabletorecognizetheirhandlerssaidProfessorJennyMortonwholedtheCambridgestudy.We'veshownwithourstudythatsheephaveadvancedface﹣recognitionabilitiescomparablewiththoseofhumansandmonkeys. RecognizingfacesisoneofthemostimportantsocialskillsforhumanbeingandsomedisordersofthebrainincludingHuntington'sdiseaseaffectthisability. Sheeparelong﹣livedandhavebrainsthataresimilarinsizeandcomplexitytothoseofsomemonkeys.ThatmeanstheycanbeusefulmodelstohelpusunderstanddisordersofthebrainsuchasHuntington'sdiseasethatdevelopoveralongtimeandaffectcognitiveabilities.OurstudygivesusanotherwaytomonitorhowtheseabilitieschangeMortonsaid. 1Accordingtothenewresearchwhat'sunusualaboutsheep? A.Theyhavelargebrains. B.Theycanrecognizetheirowners. C.Theycantellanimalsfromhumans. D.Theycanrecognizehumanfacesfromphotograph. 2Howdidtheresearcherstrainthesheep? A.Byguidingthemtofollowtheirhandlers. B.Byshowingphotosofhumansandmonkeysbyturns. C.Bygivingfoodrewards. D.Byshowingphotosoffamouspeople. 3Whatcanbeinferredfromthepassage? A.Sheephaveahigherface﹣recognitionabilitythanmonkeys. B.Thenewdiscoveryisbeneficialtothestudyofcognitiveabilitychanges. C.Thesheep'sface﹣recognitionabilitysaysthesamewhenshownphotosatanyangle. D.Thesheep'sface﹣recognitionabilitymaypreventsomedisordersofthebrain. 4What'sthebesttitleofthepassage? A.ANewdiscoveryaboutSheep. B.HowSheepRecognizeEachOther. C.AWonderfulScientist. D.TheLifeofSheep.
假设你是李华你的英国网友Jack正在学习汉语他在信中询问你如何提高汉语写作能力.请你用英语给他写封信就如何提高写作能力给他提些建议. 内容要点如下 1.多读别人的文章Chinesearticles 2.多写多练 3.不要害怕出错. 4.其他 注意1.词数100左右2.可适当增加细节以使行文连贯.
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