陜西省咸陽中學(xué)2025屆高三一診考試英語試卷含答案

陜西省咸陽中學(xué)2025屆高三一診考試英語試卷含答案注意事項(xiàng)：1．答卷前，考生務(wù)必將自己的姓名、準(zhǔn)考證號、考場號和座位號填寫在試題卷和答題卡上。用2B鉛筆將試卷類型（B）填涂在答題卡相應(yīng)位置上。將條形碼粘貼在答題卡右上角"條形碼粘貼處"。2．作答選擇題時，選出每小題答案后，用2B鉛筆把答題卡上對應(yīng)題目選項(xiàng)的答案信息點(diǎn)涂黑；如需改動，用橡皮擦干凈后，再選涂其他答案。答案不能答在試題卷上。3．非選擇題必須用黑色字跡的鋼筆或簽字筆作答，答案必須寫在答題卡各題目指定區(qū)域內(nèi)相應(yīng)位置上；如需改動，先劃掉原來的答案，然后再寫上新答案；不準(zhǔn)使用鉛筆和涂改液。不按以上要求作答無效。4．考生必須保證答題卡的整潔?？荚嚱Y(jié)束后，請將本試卷和答題卡一并交回。第一部分（共20小題，每小題1.5分，滿分30分）1．Whileintheuniversity,wewereofferedanumberofafter-schoolactivitiestooursocialskills.A．createB．growC．settleD．develop2．Sofar,morethan1300hotelsinEurope,Africa,MiddleEastregionhavecommittedto_________intheevent,withmanymore________tojointheeffort.A．participating;expecting B．participate;toexpectC．participating;expected D．participate;tobeexpected3．Trytobeindependent,foryourparentscan'tdo________foryouallyourlife.A．something B．nothingC．everything D．a(chǎn)nything4．Somepeopleusehand-writtenletters______typingbecausethey’remorepersonalandrepresentyoursincerity.A．inpreferencetoB．inprocessofC．inreferencewithD．insearchof5．－Thezookeeperwasreallyannoyedwithme.－Howcouldhehavebeenifyou____stonesattheanimals?A．didn’tthrow B．don’tthrowC．hadn’tthrown D．haven’tthrown6．Whetherthebuildingsinthisareashouldbepulleddownhasremained____；peoplearestilllookingforotherpossiblesolutions.A．unchallenged B．relevantC．controversial D．contradictory7．Heisabad-temperedfellow,buthe________bequitecharmingwhenhewishes.A．shall B．shouldC．can D．must8．It’scertainlyhardwork.But,amanwhowishestohaveacareerhastomakeagreatmanysacrifices.A．onthecontrary B．inaddition C．ontheotherhand D．inthatcase9．Ifyoucandowhatyou’reweakest______,youcanhandleanychallenge.A．forB．a(chǎn)tC．withD．to10．—HowdoyoufindyourtriptoSanyaduringthethree-dayNewYearHoliday?—________Ican’tspeaktoohighlyofit.A．Oh,wonderfulindeed!B．It’sawful!C．Don’tmentionit．D．Yousaidit.11．We__________backinthehotelnowifyoudidn’tlosethemap．A．a(chǎn)re B．wereC．wouldbe D．willbe12．Weshoulddowhatwecan______people’shardworkpaysoff.A．besure B．beingsureC．makingsure D．tomakesure13．Paulcouldbeaveryattractiveboybuthe______tohisbehaviour.A．paidnoattention B．werepayingnoattentionC．paysnoattention D．hadpaidnoattention14．Mr.Zhanggavealltextbookstoallthepupils,except____________whohadalreadytakenthem.A．theseB．onesC．thoseD．theothers15．Look,____fashionableclothesisshewearingthatalltheeyesarefixedonher!A．so B．such C．how D．what16．Therearemanyfamousculturalrelicsinourcountry,many_______thousandsofyearsago.A．datingbackto B．datebacktoC．datedbackto D．weredatedbackto17．“MadeinChina2025”aimstotransformChinafromaproduct-makingfactoryintoaproduct-makingpower,______________drivenbyinnovationandemphasizingqualityoverquantity.A．theonethat B．onethatC．one D．theone18．_____tomanagetimewisely,andyoucanmakethemostoutofeachday.A．LearningB．TolearnC．LearnedD．Learn19．Thefirstsnowdidn’tfalluntilFebruaryinourprovincethisyear,________wasunexpected.A．it B．which C．that D．what20．I’mverygratefultomyhighschoolteachers,without______helpIwouldn’tbesoexcellent.A．whom B．their C．which D．whose第二部分閱讀理解（滿分40分）閱讀下列短文，從每題所給的A、B、C、D四個選項(xiàng)中，選出最佳選項(xiàng)。21．（6分）Parentscomplainthatchildrenoutgrowtheirclothessofastthatitcostsafortune（￡12，000onaverageperyear），goingthroughsevendifferentsizesinthespaceoftheirfirsttwoyears．Therecouldnowbeasolution：anewhigh－techfabric（織物）thatexpandsasthewearergrows．RyanYasin，whoisstudyingforamaster’sdegreeattheLondonRoyalCollegeofArt，cameupwiththeideaafterpurchasingclothesforhisnewbornnephew，onlytofindthebabyhadoutgrownthembythetimetheyarrived．InadditiontotheexpenseYasinwasalsoconcernedabouttheenvironmentalinfluence．Theprocessofmakinganddistributingjustlkilogram，or2．2pounds，ofnewfabricresultsinanaverageof23kg，or50poundsofgreenhousegases．Tomakemattersworse，the“fastfashion”trendworldwidehascausedgarmentproductiontodoublesince2000，withmorethanhalfoftheclothingendingupinlandfillsannually!Tofindasolution，Yasinusedhispreviousexperiencedesigningsatellitestoinventawaytofoldsynthetic（合成的）materialsuchthatitstretchesinalldirections．Thefirstdesign，apairoftinypants，notonlyfithisbabynephew，butalsohis2－year-oldniece!Afterspendingalotoftimeperfectingtheprocessandtestingthedesign，Yasinisnowawaitingapatentforhisdesignandseekinginvestors（投資者）tobringtheclothingtomarket．ForhisnewlineofPetitPli，thedesignerplanstoproduceouterwearthatisbothwaterproof（防水的）andwindproof．Theclothingwillbemachinewashableandfoldsmallenoughtofitinajacketorpantpocket．Yasinplanstoestablishatake－backsystemsothatworn－outPetitPliclothingcanberecycledintonewfabric．Thedesignerdoesnotexpectparentstodresstheirchildrenonlyinhisexpandableclothing，particularlysincethecurrentdesignsusesyntheticmaterials．Butheplanstosoonproducethewearin“awidervarietyofgarments”andhopesthatPetitPliwillbeabletohavean“influenceonover-consumption．”Wesurelyhopehesucceeds!1、WhatinspiredYasin’sinvention?A．Hisgreatexpenseonclothes．B．Hisunhappyexperience．C．Hisnephew’spiled-upclothes．D．Hisdesireforamaster’sdegree．2、WhichofthefollowingstatementsaboutYasin’sdesignistrue?A．Ithasbeentestedsuccessful．B．Ithascomeonthemarket．C．Ithasgotapatent．D．Ithasattractedalotofinvestors．3、Whatwillbeoneadvantageofthenewouterwear?A．Itcomesinvariousstyles．B．Itneedsnowashing．C．Itcanneverbewornout．D．Itisspace－saving．4、WhydoesYasinsuggestalimiteduseoftheexpandableclothing?A．Itscostistoohigh．B．Itlacksstylishdesigns．C．Itsmaterialsarenotnatural．D．Itisnoteasilyrecycled．22．（8分）Lackofinexpensive,reliableenergydeliveryisoneofthechiefbarrierstogrowthanddevelopmentinsub-SaharanAfrica.Nearlyseventypercentofpeoplelivingintheregionlackaccesstoelectricity,forcingthemtospendsignificantamountsoftheirincomeoncostlyandunhealthyformsofenergysuchasdiesel(柴油)fueltorungeneratorsandkerosene(煤油)forlanterns.ButifthereisonethingAfricaisnotlacking,itissunshine.Andthatmeansalot;indeed,forsomeoftheworld’spoorestpeople,itmakesallthedifferenceintheworld.Alittlemorethanayearago,PowerAfrica—aU.S.Governmentinitiative(倡議)coordinatedbytheU.S.AgencyforInternationalDevelopment,orUSAID—andPowerAfrica’spartners,theUnitedKingdomDepartmentforInternationalDevelopment,ShellFoundation,andtheAfricanDevelopmentBank,startedtheScalingOff-GridEnergyGrandChallengeforDevelopment,withafocusonpay-as-you-gosolarhomesystems.TheChallenge’sgoalistoprovide20millionoff-grid(離網(wǎng))householdsinsub-SaharanAfricawithclean,affordableelectricityby2030.Sofar,theChallengehasmade40-plusinvestmentsinearly-stage,off-gridenergycompanies,whichareexpectedtoresultinsome4.8millionnewelectricalconnections.Onereasonforthesuccessofthestart-upcompaniesthathavewongrants(資助)fromtheChallengeisthefactthatthecostofsolartechnologyisfallingfast,soitiswithinthemeansofthosewholiveawayfromtraditionalpowergrids.Andthankstothenewsystemofmobilemoneyandpay-as-you-gofinancing,theycanpurchasethesolarpower-generatingequipmenttheyneedandpayforitindailyinstallments(分期付款)fromtheirtelephones,foraslittleas15centsaday.Thankstothesetechnologicalandfinancialinnovations(創(chuàng)新),manypeoplearegettingelectricityforthefirsttimeeveryday.Inthesenewly-electrifiedcommunities,businessescanboom,clinicscansafelystorevaccinesandstudentsmaystudylongafterdark.Indeed,accesstocleanandreliableelectricitycanenableentirecommunitiestoescapethecycleofextremepoverty.1、Whatisthemainproblempeopleinsub-SaharanAfricaarefacedwith,accordingtoParagraph1?A．Theyarelackofelectricity.B．Theyarelackofdieselfuelandkerosene.C．Theyarelackofmoney.D．Theyarelackofsunshine.2、What’stheaimofPowerAfrica?A．Tomakepeoplericher.B．Tomakepeoplehealthier.C．Toprovidepeoplewithcleanfoodandwater.D．Toprovidepeoplewithinexpensiveelectricity.3、WhichisNOTthereasonforthesuccessofthestart-upcompanies?A．Thecostofsolartechnologyisdropping.B．Theyliveawayfromtraditionalpowergrids.C．Theycanusethenewsystemofmobilemoneyandpay-as-you-gofinancing.D．Theycanpayfortheequipmentindailylowinstallments.4、Thetextisespeciallyhelpfulforthosewhocareabout________.A．a(chǎn)gricultureB．environmentC．technologyD．education23．（8分）“Preventingobesity(肥胖)andsmokingcansavelives,butitdoesn’tsavemoney,”reportedresearchers.“Itwasasmallsurprise,foritisagainstthecommonbelief,”saidPietervanBaal,wholedthestudy.“Butitmakessense.Ifyoulivelonger,thenyourcostsofthehealthsystemwillbemore.”Theresearchersfoundthatfromage20to56,obesepeoplerackedup(累計(jì))themostexpensivehealthcosts.Butonaverage,healthypeoplelived84years.Smokerslivedabout77years,andobesepeoplelivedabout80years.Smokersandobesepeopletendedtohavemoreheartdiseasethanhealthypeople.Thereforeinthelongrun,thethinandhealthygroupspentabout$417,000,fromage20on.Smokersspentabout$326,000andobesepeople$371,000.“Theresultthrowsabucketofcoldwaterontotheidea,basedonguesswork,thatobesityisgoingtocosttrillionsofdollars,”saidPatrickBasham,aprofessorofhealthpolitics.“Ifwe’regoingtoworryaboutthefutureofobesity,weshouldstopworryingaboutitsfinancialimpact,”hesaid.“Thebenefitsofobesitypreventionmaynotbeseenimmediatelyintermsofcostsavingintomorrow’sbudget,buttherearelong-termgains,”saidBaal.“Theseareoftenimmeasurablewhenitcomestopeoplelivinglongerandhealthierlives.”Inthemeanwhile,hesaidthatgovernmentsshouldrecognizethatsuccessfulsmokingandobesitypreventionprogramsmeanthatpeoplewillhaveahigherchanceofdyingofsomethingmoreexpensivelaterinlife.“Lungcancerisacheapdiseasetotreatbecausepeopledon’tsurviveverylong.ButiftheyareoldenoughtogetAlzheimer’s(早老性癡呆病)oneday,theymaysurvivelongerandcostmore.Wearenotadvisingthatgovernmentsstoptryingtopreventobesity,”Baalsaid.“Buttheyshoulddoitfortherightreasons.”1、Amongmiddle-agedpeople,whosecostsofthehealthsystemarethemost?A．Thosewhoareheavysmokers.B．Thosewhoareoverweight.C．Thosewhoaretoothin.D．Thosewhoaresufferingfromheartattacks.2、Whatcanweknowaboutthebeliefthatobesitycostsmuch?A．Itturnsouttobeincorrect.B．Itcomesfromscientificstudies.C．Itisbasedonmedicalevidence.D．Ithaschangedoverthepastyears.3、Accordingtothetext,governmentsshouldpreventobesityforthepurposeof.A．reducingtheriskofsufferingcancerB．weakeningobesity’sfinancialimpactC．makingsureofpeople’slongandhealthylifeD．reducingthemoneyspentonmedicalprograms4、Whatwouldbethebesttitleforthistext?A．ARecentMedicalStudyShowstheTruthaboutHealthB．PreventingObesityandSmokingMayCostMoreC．ObesityandSmokingLeadtoExpensiveDiseasesD．GovernmentsChangeAttitudetowardsObesityandSmoking24．（8分）Scientiststhinkthatgrowinggardengrasscouldbethesecrettosolvingourenergyneeds,andwemaysoonbeabletoreplaceourgasolinewith“grassoline”.Theteam,includingexpertsfromCardiffUniversityinWales,hasshownthathydrogencanbetakenfromgrassinusefulamountswiththehelpofsunlightandacheapcatalyst(催化劑)—somethingthatspeedsupachemicalreactionwithoutbeingusedup.Itisthefirsttimethatthishasbeenshownanditcouldleadtoasustainable(可持續(xù)的)wayofmakinghydrogen,reportedAsianNewsInternational.Thiscouldbeanimportantkindofrenewableenergybecauseitishighinenergyanditdoesnotgiveoutharmfulgaseswhenitisburned.Studyco-authorMichaelBowkersaid,“Thisisreallyagreensourceofenergy.Hydrogenisseenasanimportantfutureenergycarrierastheworldmovesfromfossilfuelstorenewableenergy,andourresearchhasshownthatevengardengrasscouldbeagoodwayofgettingit.”Cellulose(纖維素),whichisakeypartofplantsandthebiopolymer(生物聚合物)foundinthelargestnumbersontheearth,couldbeagreatsourceofhydrogen.Initsstudy,theteamlookedatthepossibilityofgettinghydrogenfromcelluloseusingsunlightandasimplecatalyst.Thisiscalledphotocatalysis(光催化作用)andinit,thesunlightstartsthecatalyst,whichthenmakescelluloseandwaterintohydrogen.Theresearchersstudiedtheeffectivenessofthreemetal-basedcatalysts,ofwhichnickel(鎳)especiallyinterestedtheresearchers,asitisamuchmorecommonmetalthangoldandpalladium(鈀)anditsavesmoremoney.AccordingtoBowker,producinghydrogenfromcelluloseusingphotocatalysishasnotbeenstudiedindetail.Theteam’sresearchshowsthatlargeamountsofhydrogencanbeproducedusingthismethodwiththehelpofabitofsunlightandacheapcatalyst.Thestudyshowsthatitiseffectivetouserealgrasstakenfromagarden.“Thisisimportantasitavoidstheneedtoseparateandcleanupcellulose,whichcanbebothdifficultandcostly,”saidBowker.1、Whatareneededtogethydrogenfromgrass?A．Acatalystandpalladium. B．Waterandcellulose.C．Sunlightandabiopolymer. D．Sunlightandacatalyst.2、Whyisthenewwayofmakinghydrogenconsideredsignificant?A．Itischeap,greenandsustainable.B．Itisthebesttoproducetherenewableenergy.C．Itismoreproductiveandefficientthanothermethods.D．Itcanreplacethewaytomakefossilfuelscompletely.3、Whydoesnickelinteresttheresearchersinmakinghydrogenfromcellulose?A．Itcanproducethelargestamountofhydrogen.B．Itcanavoidseparatingandcleaningupcellulose.C．Itismorecommonthanothermetalsandcostsless.D．Itworksquickerthanothermetalsduringphotocatalysis.4、Whatdoestheauthorintendtotellusmainlyinthispassage?A．Catalyststhatcouldbetakenfromgrass.B．Anewwayofmakinghydrogenfromcellulose.C．Thepotentialofhydrogenasarenewableenergy.D．Theconnectionbetweenhydrogenandphotocatalysis.25．（10分）Dr.ArielBrahmanisnotjustanordinaryteacher.HewasaheadmasteratSMULabschoolJakarta(seniorhighschool).HeisalsoanExecutiveChairmanoftheIndonesianNatiocalCommissionforUNESCO.Asateacher,he’sclosetohisstudents.HealwayssparessometimetorunwithuseveryFridaymorning(ourschoolactivity)andtocomeandvisithisstudentsinclass,justtosayhi.Hosfavouritesayingsare,“Students,putsomepicturesinthebackofyourclassroom…”and“Haveanicestudy.”Healsoencourageustobefriendly,forexample,toshakehandswithoneanothereverymorning,justtosaygoodmorningtooneanotheroratleastsmileatotherpeople.Simple,butmeaningful.Dr.ArielBrahmanissofriendly.Heshowsrespecttootherandappreciatesothers.Butmostofall,thereasonwhyIlikehimissothathealwaysencouragesthechoir(唱詩班)groupatmyschooltokeeponsinging.Hehasalwayssupportedusandputhistrustinus.It’sbecauseofhimthatthechoirremainsinexistenceafterwenearlygaveupwhenfacingotherpeople’scriticism.Dr.ArielBrahmanisanationalist,especiallyineducation.AsImentionedabove,heisamemberofUNESCOforIndonesianeducation.HeisquittinghisjobastheheadofUniversitasNegeriJakartatofulfillhisdutyatUNESCO.MygrandmotheroncetoldmethatDr.ArielBrahmanwasheldinjailbecausehesaidsomethingabouthumanrights(Idon’tknowexactlywhatitwas),butunfortunately.Socharto,whowasthepresidentofIndonesia,didn’tlikethatandputDr.ArielBrahmaninjail.Well,IthinkthatisonebraveactforDr.Arielrahmantospeakhismindfreelywithouthesitatingbecauseofwhatotherpeoplemightthink.Thewayherespectsother,thewayhespeakshismindandthewayheencouragesusmakehimaninspirationforusall.1、WhichofthefollowingwordscanbestdescribeDr.ArielBrahman?A．ModestandhumorousB．BraveandkindC．Generousandpositive.D．Cautiousandkind-hearted.2、Whatcanbeinferredfromthepassage?A．Thestudentsdon'trespectDr.ArielBrahman.B．Thechoirgroupusedtobeunpopularintheauthor'sschool.C．DrArielBrahmandoesn'tlikethepresidentofIndonesia.D．TheauthorrespectsDrArielBrahmanasheisstrictwithstudents.3、WhywasDrArielBrahmanputinjail?A．Hedidn'ttakechargeofUniversitasNegeriJakarta.B．Heinspiredpeopletogoagainstthegovernment.C．Hedidn'tlikethepresidentofIndonesiaatthattime.D．HeencouragedIndonesianstofightfortheirrights.第三部分語言知識運(yùn)用（共兩節(jié)）第一節(jié)（每小題1.5分，滿分30分）閱讀下面短文，從短文后各題所給的A、B、C和D四個選項(xiàng)中，選出可以填入空白處的最佳選項(xiàng)．26．（30分）LunchhouriscrazyatSAMECafe,the40-seatrestaurantmyhusbandandIruninDenver.Awomanina(n)1suitsteppedin."Hi,Libby."shesaid.Wow,whata2!Thefirsttimeshecametothecafetwoyearsago,shehadnomoneytopay.3manycustomers,shevolunteeredtowashdishesand4Lookathernow:confidentandhopeful.Wasn'tthiswhatwe'dhopedfor?In2003,we'd5thiscrazydream:startarestaurantwithadonationboxinsteadofacashregister.Rightawaywehithurdles（阻礙）."Thereisnosuchthingasa6lunch,"onepotentiallandlordsniffed.Imetbrokers,bankersandsuppliers,onlytowatchthem7,shakingtheirheads.Nobankwouldlendusthemoneytoopenarestaurantwithno8Theonlyfundwecouldgetwasourindividualretirementaccount.9werentedspacefromalandlordonColfaxStreet.Weputflyers（傳單）aroundtheneighborhood,askedfriendsto10theword,andheldourbreath.Wordtraveledfast,11storiesinthepapersandonTV.Soonwehadmorethan50customersaday.Afewatewithoutpayingor12anhourofwork.Butmostgavewhattheycould,13itwasjustadollar.Thosewithmoneygave,andthenmore.Oneofourcustomerslefta14for500dollars.Anotherbought1000dollarsingiftcertificates.15anotherdonatedatrucksowecouldtransport16fromsuppliers.Peoplecameherepartlyforwhatourcafe17—SAME:SoAllMayEat.Wetreateveryonewith18Wehopedtodevelopasenseofcommunitysothatwemight19oneanother.Thewomaninbusinesssuitwasoneofthem.Our20toopenthecafewasworthit.1、A．dinner B．evening C．business D．summer2、A．change B．beauty C．fool D．coincidence3、A．With B．Like C．Besides D．Towards4、A．wait B．sing C．perform D．sweep5、A．lived B．hatched C．ignored D．a(chǎn)chieved6、A．packed B．delicious C．free D．delivered7、A．crowdtogether B．floodin C．walkaway D．turnup8、A．staffsupport B．regularcustomers C．lunchboxes D．cashregister9、A．Unfortunately B．Finally C．Interestingly D．Illegally10、A．a(chǎn)nalyze B．read C．spread D．a(chǎn)pprove11、A．thanksto B．a(chǎn)partfrom C．a(chǎn)headof D．a(chǎn)ccordingto12、A．regretting B．gaining C．donating D．balancing13、A．onlywhen B．a(chǎn)ndforever C．sothat D．evenif14、A．reward B．check C．bill D．list15、A．Still B．Instead C．Otherwise D．Thus16、A．lunch B．customers C．dishes D．produce17、A．stoodfor B．a(chǎn)ppliedfor C．benefitedfrom D．dependedon18、A．patience B．generosity C．confidence D．dignity19、A．protect B．trust C．help D．treasure20、A．dream B．struggle C．management D．Style第二節(jié)（每小題1.5分，滿分15分）閱讀下面材料，在空白處填入1個適當(dāng)?shù)膯卧~或括號內(nèi)單詞的正確形式。27．（15分）Manyofusenjoymusicbecauseofthewayitmakesusfeel.Butforchimps（黑猩猩）,it’snothingmorethanalotofnoise.ScientistsfromtheUniversityofYork,UK,foundthatchimpsdon’tappreciatelisteningtomusic,despitetheirDNA1．(be)96to98percentsimilartothatofhumans.Inthestudy,a“jukebox（自動唱機(jī)）”2．(create),whichallowedchimpstoselecttheirfavoriteclassical,poporrockmusic,or3．(simple)tochoosesilence.Theanimalswalkedawayfromthemusictheyseemedtodislikethemost.Thestudyfoundtheywerelesslikely4．(walk)awayfromclassicalmusiclikeMozartthanfast-pacedpopsongslikethoseofJustinBieber’s.EmmaWallacefromtheUniversityofYorktoldtheDailyMailthatthefast-pacedrhythmmayhavebeen5．turnedthechimpsoff.“6．it’smorepossibleforthechimpanzeestoleavetothefastermusic,theydidnotshow7．a(chǎn)ctualpreferencefortheslowerclassicalmusic,”saidWallace.“Infact,theyseemtobeindifferenttoboth8．(both)ofmusic.”Theseresultssuggestedthatmusic9．(appreciate)maybesomethingthatisunique10．humans,accordingtoWallace.第四部分寫作（共兩節(jié)）第一節(jié)短文改錯（滿分10分）28．（10分）假定英語課上老師要求同桌之間交換修改作文，請你修改你同桌寫的以下作文。文中共有10處語言錯誤，每句中最多有兩處。每處錯誤僅涉及一個單詞的增加、刪除或修改。增加：在缺詞處加一個漏字符號（∧），并在其下面寫出該加的詞。刪除：把多余的詞用斜線（\）劃掉。修改：在錯的詞下劃一橫線，并在該詞下面寫出修改后的詞。注意：1.每處錯誤及其修改均僅限一詞；2.只允許