河北省石家庄二中2019-2020学年高一4月月考英语试题

石家庄二中20192020学年第二学期高一年级4月月考自主测试高一英语（时间：60分钟满分：100）第一部分阅读理解（共两节，满分40分） 第一节（共15小题;每小题2分，满分30分）阅读下列四篇短文，从每小题后所给的A、B、C、D四个选项中,选出最佳选项。AWhilesmartphonesstandaccusedofavarietyofcrimes,thesepocketputerscancertainlybeaforceforgood.Yourphoneisalwayswithyou,makingittheperfectdevicetopushyouintoamorebeneficialwayofliving.Herearesomeofthebestappsthatcanhelp.HabiticaHabiticaturnsthegoalofforminggoodhabitsintoagame,withitsowncharactersandscoring.It’salotoffun,andtheappalsoletsyoubuildhabitswithfriendsandfamily.Inadditiontoregularrepeatinghabits,youcanaddamoregeneralto­dolist,andtherewardsyougetcanbecustomizedtoo—youcouldtreatyourselftoamealoutoranextrahourofgames.SmokeFreeIfyou’vegotaspecifichabitinmindyou’llusuallyfindspecificappstohelp,likeSmokeFree.Ifyou’redeterminedtogiveupsmoking,thisisoneofthemostprehensiveappsforgivingyouthatextrapushyouneedtomakeapermanentchange.Theappoffersahostofusefulfeaturestopeoplewantingtogosmoke­free:theabilitytoseeyourprogressovertime,chartsshowinghowyourhealthisimproving,day­by­dayencouragement,andsomeadviceontechniquesforgivingupsmoking.MyFitnessPalYoucanfindtonsofhealthandfitnessappsforyourphone,butMyFitnessPalstandsoutnotjustbecauseitiseasytouse,butbecauseitmakespracticalsuggestionsforyou.Itcantakeinahostofdata,fromthecalories(卡路里)you’retakingintothenumberofswimsyou’redoingperweek,andofferreportsoncalorieconsumptionandmacronutrient(大量营养素)breakdown.1．WhatcanHabiticahelpyoutodo?A．Winatoughgame. B．Startalastingfriendship.C．Findafancyrestaurant. D．Developapleasanthabit.2．WhichofthefollowingcanSmokeFreeprovide?A．Thefreedomtosmoke. B．Theabilitytomakeprogress.C．Adviceonhowtoquitsmoking. D．Chartsaboutyourexcellenthealth.3．Whatcanwelearnaboutthethreeappsmentionedinthetext?A．They’recheap. B．They’repractical. C．They’refree. D．They’reinteresting.BIttookmultipleweddingsforChristineLawtorealizewhatsheneededtodo.Inthesummerof2014,herschedulewaspackedwithfriends’marriagecelebrations—flower­filledoccasionsthatgotherthinking,“Wheredoalltheflowersgoaftertheparty？”Moreoftenthannot,theywerethrownaway.Lawwasconfidentshecouldfindabetteruseforthem.ByAugust,shehadaplan：convincecouplesandpanieshostingeventstodonatetheirflowers,whichshewouldpickupanddeliverwithin48hourstoseniorsacrossthecity.Shewantedtobringbeautyintothelivesoftheelderly.Shedrewonherexperiencethroughbeingavolunteerinnon­profitinstitutionsinordertosetupherownorganization,whichshecalledFloranthropie.Nothavingenoughbouquets(花束)forall150peopleofahealthcenter,Lawaskedthestafftoprovidealistofpatientswhoneededcheeringupmost.“ThefirstwomanIapproachedthoughtitwasamistake,andthattheflowerscouldn’tpossiblybeforher，”saysLaw.“Isaidtheywereagift,andwetalkedforahalfhour.”Inadditiontohealthcenters,Floranthropiefocusesonmunitygroupsdevotedtotheelderly.LaëtitiaThélèmeisavolunteerforLesPetitsFières,anorganizationthataimstohelptheelderlywhodon’thaveasupportsystem.ThegroupreceivesadozenorsobouquetsfromFloranthropiemonthly,andthenredistributesthem.“Ourmottois‘flowersbeforebread’，”saysThélème.“Wedon’tfocusonprimarycare,butratheronnourishing(滋养)thespirit.Floranthropiehelpsusdothat.It’samazingwhatabigdifferenceasmallbouquetcanmake.”Inthebeginning,mostofFloranthropie’sdonationscamethroughwordofmouth.Thesedays,Lawreceivesmessagesfromstrangersviaherorganization’sFacebookpageandhasconnectedwithcorporationsandflowerwholesalers.LawhopestoexpandFloranthropienationally,butatthispointishappytobeabletooverseeeachdeliverypersonally.4．WhatmadeChristineLawsetupFloranthropieA．Thewasteofflowers. B．Thelonelinessofseniors.C．Thepersuasionofotherfriends. D．Thewarmatmosphereofweddings.5．Whatwasthewoman’sreactiontoChristineLaw’sflowers?A．Shewasmoved. B．Shewasexcited. C．Shewasworried. D．Shewassurprised.6．WhatcanweinferaboutFloranthropiefromLaëtitiaThélème’swords?A．Itshouldfocusonprimarycare. B．Itisbenefitingmorethantheelderly.C．Itisdoingsomethingofgreatimportance. D．Itshouldcooperatewithmorenon­profitinstitutions.7．Whatisthebesttitleforthetext?A．VolunteerYourTime B．Don’tThrowFlowersAwayC．SpecialDeliveryMakesYourDay D．BrightenSeniors’LiveswithFlowersCYoutrytokeepyoureyeswideopenwhilewatchingabasketballmatchorawonderfulfireworkshowincaseyoumightmisssomethingexcitinginjusttheblinkofaneye.Butinfact,humansblinkabout15timesperminuteonaverage.Haveyouevermissedanythingbecauseyoublinked?Probablynot.Whyisthat?AccordingtoanewstudypublishedinthejournalCurrentBiologyinSeptember,ourbrainhastheabilitytoskipthetemporarydarknesswhenweblink.Itcankeepvisualinformationforashortperiodoftimeandthenputittogethertoformanimagewithoutinterruption.Inordertounderstandhowthisworks,agroupofscientistsattheGermanPrimateCenterandtheUniversityMedicalCenterGottingeninGermanyconductedanexperiment.Inthestudy,theparticipantswereaskedtolookatpatternsonascreenwhosedirectioncouldbeinterpretedindifferentways,suchashorizontally(水平地)orvertically(垂直地).Whenonepatternwasabouttodisappearandthenextonewasabouttoe,theparticipantshadtoindicatethedirectionthatthenextpatternwouldappear.Theresearchersfoundthatwhenthedirectionsoftwopatternsdidn’tmatch,theareainourbrainwhichisresponsibleforvisualmemorywasactivated.Thissameareashowedlessactivitywhentwopatternswereinthesamedirection.“Themedialprefrontalcortex(前额叶皮层)adjustscurrentvisualinformationwithpreviouslyobtainedinformation,andthusenablesustoperceivetheworldwithmorestability,evenwhenwebrieflycloseoureyestoblink,”CasparSchwiedrzikexplainedinScienceDaily.HeisthefirstauthorofthestudyandalsoascientistattheGermanPrimateCenter.8．Wedon’tmissanythingwhenblinkingbecauseourbraincan________．A．dealwiththemissingimage B．rememberallthatweseeC．imaginewhatoureyesmiss D．putourpiecesofmemorytogether9．Whatdoestheunderlinedword“it”inParagraph2referto?A．Ourbrain. B．Visualinformation. C．CurrentBiology. D．Thetemporarydarkness.10．Whatdoweknowabouttheexperiment?A．Thetwopatternsappearatthesametime. B．Visualmemorycanbemoreactivatedbysimilarity.C．Participantscaninterpretpatternsdifferently. D．Thedifferentdirectionsactivatedvisualmemory.11．Whatwouldbethebesttitleforthispassage?A．TheBrain’sStructure B．TheBrain’sActivatedPatternsC．TheBrain’sSpecialSkill D．TheBrain’sReactionDInthestoryoftheCrowandthePitcherfromAesop’sFables,athirstycrowdropsstonesintoanarrowjartoraisethelowlevelofwaterinsidesohecantakeadrink.Nowscientistshaveevidencetobackupthatstory.Crowsactuallydounderstandhowtomakewaterdisplacement(排水量)worktotheiradvantage,experimentsshow.Theresultssuggestthatthebirdsare,atleastinsomeaspects,assmartasfirst­graders.Researchers,ledbySarahJelbertattheUniversityofCambridge,presentedsixcrowswithtubescontainingwater.Insidethetubes,awormorapieceofmeatonapieceofwoodwasfloating,justoutofreachofthecrow.Infrontofthetubes,theresearchersarrangedseveralrubbererasersthatwouldsink,andsomeplasticobjectsthatwouldfloat.Thecrowsfoundoutthattheycoulddroptheerasersintothetubesinordertoraisethewaterlevelandgettheirsnack.However,thebirdshandledawkwardlyinexperimentsinwhichtheycouldchoosetodropobjectsineitherawidetubeoranarrowonetogetasnack,theresearcherssaid.Droppingobjectsintoanarrowtubewouldliftthewaterlevelbyagreateramountandputthetreatwithinreachafterjusttwodrops;whileittookaroundsevendropstoraisethesnacktothesamelevelinthewidetube.Thecrowsobviouslydidn’trealizethis,andmostofthemwentforthewidetubefirst.Previousstudiesshowedthatchimpsandhumanchildrencansolvesimilartasks.Ina2011study,chimpsandkidsfoundoutthattheycouldputwaterintoatubetoreachapeanutthatwasfloatinginasmallamountofwateratthebottom.12．HowdidthecrowsgetthesnackinSarah’sexperiment?A．Bybreakingthetube. B．Bydroppinginerasers.C．Bystandingonthewood. D．Byremovingthewood.13．Whatdoestheunderlinedpart“thebirdshandledawkwardly”meaninParagraph4?A．Theywereunabletotelldifferentshapes. B．Theydroppedobjectsonlyintonarrowtubes.C．Theywerenotawareofthesnackatfirstsight. D．Theymostlyavoidedtheeasierwaytogetthesnack.14．Whatdoesthetextmainlyfocuson?A．StoriesofAesop’sFables. B．Thedevelopmentofcrows.C．Crows’intelligence. D．Human­animalmunication.15．Whatdoweknowaboutcrowsinthepassage?A．Crowsarealmostascleverasfirst­gradersinsomeaspects.B．Crowsunderstandwaterdisplacementpletely.C．Chimpsandchildrenaremuchsmarterthancrows.D．ThestoryoftheCrowandthePitcherlacksevidence.第二节七选五(共5小题；每小题2分，满分10分)根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。WaystoFinallyBeeaMorningPersonCalculateyourperfectbedtimeTheeasiestwaytowakeupearlierinthemorningistogetenoughsleep.16:Foraweek,rememberthenumberofhoursyousleep,includingweekends.Dividethatnumberbyseventocalculateyournightlyneed.Thinkaboutatimeyou'vebeenonvacationorofanightyoufeltparticularlyrested—howmuchsleepdidyouget?Onceyouhavethatnumber,calculatebackwardsfromthetimeyouwanttogetupandplantogotobedatthatnewhour.Findoutyourstay­awakethingsNighttimecangoawayfast,especiallywhenyouhavealottoacplish.Tobesuccessfulinhavinganearlierbedtime,youmayneedtosetanalarm.Andcontrarytopopularadvice,youdon'thavetoturnoffthelightrightbeforebed.17,butreadingathrillermaynotbethebestidea.Createamorningto­dolistAnothergoodhabitistothinkaboutwhatyouwanttoacplishinthemorning.Havingamorninggoalisthebestmotivation（动力）.18Thiswayyou'llfeellikeyou'reonataskwhenyouwakeup,you'llgetclosertoyourmorninggoalandyou'llhaveaclearscheduletofollow.19Peoplewhoexerciseareeasytosleepbetterthanthosewhodon't.Indeed,studieshaveshownastrongconnectiontoabetterqualityofsleepforpeoplewhoworkoutatleast10minutesaday.20,whichinturnhelpsfightwithsleeplessness.A.PraiseyourselfB.TakesomeexerciseC.ReadingisagreatwaytorelaxD.WritethreetasksyouhavetodothenextdayE.Here'showtofigureoutyoursleepneedsF.Onereason:exercisereducesyourstresslevelsG.Itcanbedifficulttodevelopanewhabitevenifyouknowthehabitispositiveanduseful第二部分语言知识运用(共两节，满分50分)第一节(共20小题；每小题1.5分，满分30分)阅读下面短文，从短文后各题所给的A、B、C和D四个选项中，选出可以填入空白处的最佳选项。Stevewasaseventhgrader,abigboy,lookingmorelikeateenagerthana12­year­old.Yet,hewentunnoticed—hehadbeen21everyexaminationsincefirstgrade—untilMissWilmaappeared.Inthemiddleofthefirstsemesterofschool,theentireseventhgradewas22forbasicskills.“Youalldidprettywell，”MissWilmatoldtheclassaftergoingoverthe23，“exceptforoneboy.Andit24myhearttotellyouthis,but...”she25，“thesmartestboyintheseventhgradeisfailingmyclass.”Steve26hiseyesandcarefullyexaminedhisfingertips.Afterthat,Stevestillwouldn’tdohishomework.EvenifMissWilma27punishedhim,heremained28.“Steve,please!Icareaboutyou！”29,Stevegotit!“SomeoneCARESABOUTME？！”OneMondayacoupleofweekslater,MissWilmagavea30ontheweekendhomework.Steve31throughthetestandwasthefirsttohandinhispaper.Withalookof32，MissWilmatookhispaperandbegantolookitover.MissWilma’sfacewasina33shock!SheglancedupatSteve,then34，thenup.Thesmartestboyintheseventhgradehadjustpassedhisfirsttest!Fromthatmoment,nothingwasthesameforSteve.Hediscoveredthatnotonlycouldherememberandunderstand35,buthecouldtranslatewhathelearnedintohislife.Hebecame36．Afterhighschool,SteveenlistedintheNavy,andhehada(n)37militarycareer.Duringhisnavalyears,heinspiredmanyyoungpeoplewhomightnothave38themselveswithouthim.A39tookplacewithintheheartofaboyallbecauseofoneteacher,who40abouthim.A.missingB.failing C.passing D.skipping2 B.classified C.separated D.dismissed2 B.effects C.lessons D.results2 B.presses C.breaks D.destroys2 B.hesitated C.interrupted D.laughed2 B.raised C.covered D.closed2 B.steadily C.severely D.secretly2 B.stubborn C.flexible D.crazy29．A.monly B.Unwillingly C.Particularly D.Suddenly3 B.chance C.speech D.presentation3 B.looked C.lived D.hurried3 B.surprise C.satisfaction D.inspiration3 B.total C.precious D.ridiculous3 B.away C.out D.back3 B.grades C.knowledge D.subjects3 B.lazy C.rough D.troublesome3 B.ordinary C.hardworking D.successful38．A.reliedon B.lookedafter C.turnedto D.believedin3 B.choice C.change D.campaign4 B.listened C.wished D.cared第二节语篇填空(共10小题；每小题2分，满分20分)阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。Lions,tigersandotheranimalsarestayingawakeatnight41(avoid)humanbeings,anewstudyfinds.Scientistshaveknownthathumanactivitiescanleadtochangesinnature.Manyanimalsmaymovearoundlessortraveltofarplacestokeepaway42people.Bybeingawakeatnight,animalscanalsobeonguardagainstpossibleenemiesandspendlesstime43(look)forfood.Thelatestresearchfoundevenactivitieslikefarmingandcampingcan44(fright)animalsandcausethemtobeemoreactiveatnight.45hadbeenstudiedwerelionsinTanzania,tigersinNepalandmonkeysinBrazil.Researcherspared46(careful)howmuchtimethoseanimalswereactiveatnightinareasofhumanactivities,suchashuntingandfarming.47washumanactivitiesthatcausedanincreaseofabout20percentinnight­timeactivities,evenincreaturesthatusuallysleepatnight.Results48(publish)inthejournalSciencetwomonthsago.Thenewfindingsare49(usual)becausenooneelsehaslookedatitinsuchdetailbefore.EcologistMarleeTuckerwas50(surprise)thatanykindofhumanactivitiesisenoughforanimalstoseepeopleasathreat.单项选择(共10小题；每小题1分，满分10分)51.Lastmonth，anearthquake_______sixonRichterscalehappenedinthenorthernpartofIndonesia.A.measured B.tomeasure C.tobemeasured D.measuring52.Heisabreastcancer_________,whohasdevotedallhistimeandenergytostudyingit.A.specialist B.physician C.physicist D.surgeon53.Thatboyisbeingareal______.A.insect B.pest C.worm D.bacterium54.Peopleofakindetogether.Birdsofa_______flocktogether.A.leather B.fur C.moustache D.feather55.Wedon’taccepttheresponsibilitybutwewillrefundthemoneyasa______ofgoodwill.A.posture B.gesture C.state D.rank56.Itis________thatheshouldhavefailedtowintherace.A.certain B.wonder C.curious D.mess57.Hedyedhisbeardtoavoid____________.toberecognized B.beingrecognizedC.recognition D.recognizeThepetitionattractedover500players____________8differentcountries.A.torepresent B.represented C.representing D.whorepresents59.Iwasthefirstreporter________totakepicturesofgiantpandasinthereserve.A.topermit B.tobepermitted C.permitted D.permitting60.Iagreewithmostofwhatyousaid,butIdon'tagreewith_________.A.everything B.anything C.something D.nothing石家庄二中20192020学年第二学期高一年级4月月考自主测试高一英语答案第一部分阅读理解（共两节，满分40分） 第一节（共15小题;每小题2分，满分30分）A【语篇解读】本文是一篇应用文，主要介绍了三款在日常生活中很实用的软件。1．D解析：细节理解题。根据第二段第一、二句“Habiticaturnsthegoalofforminggoodhabitsintoagame,withitsowncharactersandscoring.It’salotoffun,andtheappalsoletsyoubuildhabitswithfriendsandfamily.”可知，Habitica是一款培养用户好习惯的软件，该软件有自己的角色和得分，很有趣，还可以让你的朋友和家人受益。故D项正确。2．C解析：细节理解题。根据第三段尾句中的“theabilitytoseeyourprogressovertime,chartsshowinghowyourhealthisimproving,day­by­dayencouragement,andsomeadviceontechniquesforgivingupsmoking”可知，在这款软件中，你可以看到你的进步，通过图表你可以看到健康改善的过程，此外，用户每天还可得到鼓励和一些关于戒烟技巧的建议。故C项正确。3．B解析：推理判断题。本文主要介绍了三款在日常生活中很实用的软件，包括好习惯养成软件、戒烟软件和健康与健身软件。并结合第一段中的“amorebeneficialwayofliving”可推知，B项正确。B【语篇解读】本文讲述了ChristineLaw把婚礼上用过的花送给老人们，为他们的生活增加美的享受，她的做法得到了很多人的支持。4.A解析：细节理解题。根据第一段中的“‘Wheredoalltheflowersgoaftertheparty？’Moreoftenthannot,theywerethrownaway.Lawwasconfidentshecouldfindabetteruseforthem.”可知，婚礼上使用过的花束的浪费使ChristineLaw成立了Floranthropie这个机构。故选A。5．D解析：推理判断题。根据第二段中的“ThefirstwomanIapproachedthoughtitwasamistake,andthattheflowerscouldn’tpossiblybeforher”可推知，当ChristineLaw给第一位女士送花时，她感到难以置信。故选D。6．C解析：推理判断题。根据第三段中的“Floranthropiehelpsusdothat.It’samazingwhatabigdifferenceasmallbouquetcanmake.”可推知，LaëtitiaThélème认为Floranthropie做的事产生了很大影响，故C项符合文意。7．D解析：标题归纳题。本文主要讲述了ChristineLaw为了不浪费婚礼上用过的花，把花送给老人们，给他们的生活带来了美。故D项适合作文章标题。C【语篇解读】本文是一篇说明文。研究发现眨眼并不会错过细节并解释了其原因。8．A解析：推理判断题。根据第二段第一句“AccordingtoanewstudypublishedinthejournalCurrentBiologyinSeptember,ourbrainhastheabilitytoskipthetemporarydarknesswhenweblink.”可知，九月份发表在《当代生物学》杂志上的一项新研究表明，我们的大脑有能力跳过我们眨眼时形成的暂时黑暗。据此可推知，由于我们的大脑能处理丢失的图像，所以眨眼不会让我们错过任何东西，故A项正确。9．B解析：代词指代题。根据第二段第二句“Itcankeepvisualinformationforashortperiodoftimeandthenputittogethertoformanimagewithoutinterruption.”可知，大脑可以在短时间内保存视觉信息，然后将其组合在一起形成不中断的图像，故可推知，it指代上文中的“visualinformation”，故B项正确。10．D解析：细节理解题。根据第四段中的“whenthedirectionsoftwopatternsdidn’tmatch,theareainourbrainwhichisresponsibleforvisualmemorywasactivated.Thissameareashowedlessactivitywhentwopatternswereinthesamedirection”可知，当两种模式的方向不一致时，掌握视觉记忆的大脑区域被激活；当两种模式在同一方向时，这个区域显示出较少的活动。据此可知，不同的方向能激活视觉记忆，故D项正确。11．C解析：标题归纳题。通读全文可知，本文主要介绍了一项科学研究。研究表明，眨眼不会错过细节并解释了其原因，即大脑有能力在短时间内保存视觉信息，然后将其组合在一起形成不中断的图像信息。故C项最适合作本文的标题。D【语篇解读】本文介绍了科学家通过实验对乌鸦智商的研究。12．B解析：细节理解题。根据第三段最后一句“Thecrowsfoundoutthattheycoulddroptheerasersintothetubesinordertoraisethewaterlevelandgettheirsnack.”可知，乌鸦能够把橡皮擦扔到管子里，使水位升高，然后吃到零食。故选B项。13．D解析：推理判断题。从第四段可知，实验中的乌鸦在面对粗细不同的管子时，虽然只需往细管里投两次物体就可以获得零食，而需往粗管里投大约七次物体才能够获得零食，但是乌鸦往往先去粗管那边，而没有选择更容易获得零食的细管。由此可推知，画线部分是说它们通常没有选择更容易的方式来获得零食。14．C解析：主旨大意题。根据第二段最后一句“Theresultssuggestthatthebirdsare,atleastinsomeaspects,assmartasfirst­graders.”以及下文中的实验可知，整篇文章都是围绕乌鸦的智商问题来展开的。15．A解析：推理判断题。根据第二段最后一句“Theresultssuggestthatthebirdsare,atleastinsomeaspects,assmartasfirst­graders.”可知，乌鸦在一些方面几乎跟一年级的学生一样聪明。第二节七选五(共5小题；每小题2分，满分10分)【语篇解读】本文是一篇说明文，讲述了让自己早起的终极绝招。16.E解析：根据本段小标题“Calculateyourperfectbedtime.”及下文“Foraweek...calculatebackwardsfromthetimeyouwanttogetupandplantogotobedatthatnewhour.”可知，本段建议计算出你的理想上床时间。17.C解析：根据上文“Andcontrarytopopularadvice，youdon'thavetoturnoffthelightrightbeforebed.”及下文“butreadingathrillermaynotbethebestidea.”可知，与普遍流行的建议相反，你睡觉前不必关灯。阅读是放松的好方法，但是读一部恐怖小说可不是最好的主意。18.D解析：根据本段小标题“Createamorningto­dolist.”及下文“Thiswayyou'llfeellikeyou'reonataskwhenyouwakeup，you'llgetclosertoyourmorninggoalandyou'llhaveaclearscheduletofollow.”可知，本段建议罗列好早起事宜，写出第二天要做的三项工作。19.B解析：根据下文“Peoplewhoexerciseareeasytosleepbetterthanthosewhodon't.”可知，锻炼的人往往比那些不锻炼的人睡眠质量高，故B项符合题意。20.F解析：根据上文“Indeed，studieshaveshownastrongconnectiontoabetterqualityofsleepforpeoplewhoworkoutatleast10minutesaday.”可知，事实上，研究表明，每天至少锻炼10分钟与睡眠质量高有大大的关联性。原因之一：运动可以降低你的压力水平，这反过来又有助于对抗失眠。第二部分语言知识运用(共两节，满分50分)第一节(共20小题；每小题1.5分，满分30分)【语篇解读】Steve曾经每次考试都不及格，但是MissWilma看到成绩的时候，却说他是班里最聪明的学生，而且告诉他老师非常关心他。Steve感受到老师对自己的良苦用心，从此刻苦学习，改变了自己的命运。老师对他的影响促使他用同样的方法去影响并且帮助更多的人。21．B解析：根据下文可知，Steve学习成绩很差；故可推