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在正方体ABCD A1B1C1D1中，异面直线BD1与A1D所成的角等于 ．
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在正方体ABCD－
1
1
1
1
中，与直线BD异面且成60°角的面对角线有( ) A.1条 B.2条 C.3条D.4条
在正方体ABCD-A1B1C1D1中M.N.为棱AB与AD的中点则异面直线MN与BD1所成角的余弦值
已知正方体ABCD﹣A1B.1C.1D.1中E为C1D.1的中点则异面直线AE与BC所成的角的余弦值
如图在正方体ABCD−A1B1C1D1中EF分别为BCBB1的中点则下列直线中与直线EF相交的是
直线AA
1
直线A
1
B
1
直线A
1
D
1
直线B
1
C
1
如图已知正方体ABCD—A1B1C1D1过BD1的平面分别交棱AA1和棱CC1于EF两点．
如图已知正方体ABCD—A1B1C1D1过BD1的平面分别交棱AA1和棱CC1于EF两点．
如图在正方体ABCD－
1
1
1
1
中，M.、N.分别是棱CD.CC
1
的中点，则异面直线A.
1
M.与DN所成的角的大小是( )
A.30° B.45° C.60° D.90°
如下图正方体ABCD—A1B1C1D1中M是DD1的中点0是底面正方形ABCD的中心P为棱A1B1上
如图所示在正方体ABCDA1B1C1D1中O是底面正方形ABCD的中心M是D1D的中点N是A1B1的
平行
相交
异面垂直
异面不垂直
棱长为a的正方体A1B1C1D1—ABCD中求D1到面AA1C1C的距离为
a
a
a
2a
如图所示在正方体ABCDA1B1C1D1中O是底面正方形ABCD的中心M是D1D的中点N是A1B1的
平行
相交
异面垂直
异面不垂直
已知正方体ABCDA.1B.1C.1D.1中E.为C.1D.1的中点则异面直线AE与BC所成角的余
如图在正方体ABCD－A.1B.1C.1D.1中异面直线BD1与A.1D.所成的角等于_______
.在正方体ABCD
1
1
1
1
中，E.，F.分别是线段BC，CD
1
的中点，则直线A.
1
B.与直线EF的位置关系是( ) A.相交B.异面 C.平行D.垂直
如图在正方体ABCD—A1B1C1D1中M是棱DD1的中点O是底面ABCD的中心P是棱A1B1上任
45°
90°
60°
不能确定
在正方体ABCD－A.1B.1C.1D.1中M.N.分别为A.1B.1BB1的中点则异面直线AM与C
如图在正方体ABCD﹣A1B.1C.1D.1中O是底面正方形ABCD的中心M是D1D.的中点N是A1
平行
相交
异面垂直
异面不垂直
正方体ABCD﹣A1B.1C.1D.1的棱长为2则异面直线BD1与AC之间的距离为.
在正方体ABCD一A1B1C1D1中四对异面直线AC与A1DBD1与ADA1C与AD1BC与AD1其
4对
3对
2对
1对
.如图ABCD－
1B1C1D1为正方体，下面结论错误的是（ ） A. BD∥平面CB1D1
AC1⊥BD
AC1⊥平面CB1D1
异面直线AD与CB1所成的角为60°
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10分英语课上老师要求同学相互修改作文.假设以下文章为你同桌所写请你对其进行修改.文章中共有10处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∧并在此符号下面写出该加的词. 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. Alicewasnotontimeforschoolinthismorning.Shelookedlittletiredwhenshemetherchemistry'steacherMissGreen.Sheapologizedforherbeinglately.MissGreenaskedheriftherewassomethingwrongwithher.Thegirlsaidthathewasallrightsoshedidn'thavemuchsleeplastnight.Shewenttoafootballgameandtooksomepictures.Aftershegothomeshewasbusydevelopedthem.Shestayeduptillmidnight.MissGreentoldhertogetmoresleepatnight.Alicepromisesnottodothatagain.ThenAliceshowedMissGreenherbeautifulpicture.
木质素是制浆造纸工业的副产物具有优良的物理化学特点若得不到充分利用变成了制浆造纸工业中的主要污染源之一不仅造成严重的环境污染而且也造成资源的重大浪费．木质素的一种单体结构简式如右图所示下列说法错误的是
30分RecentlyIpaidavisittoHarvardUniversitywheretherearetopclassscientistsandprofessorsandthebestacademicsystemintheworld. Iwasvery1whenIfirststeppedintothecampus校园.Wellit'snotevenreallyacampus.It's2likeanareainasmalltown.Harvard'smainbuildingsarefromthe18thcentury.Theylookveryoldand3.Youmight4saythey'realittleshabby破旧.Theydon'tfitthemodern5ofuniversityatall.Thebuildingsare6byflowersandtreessoIfeltasifIhadwalkedintoacastleoftheMid﹣Ages.ButwhenIlookedacrossthestreetthe7shopsandin﹣fashion时尚的studentsmademefeellikeIwasinthe21stcentury8.Itcreatesastrongcontrast对比andbringsaspecial9Ourtour10Garytookusaroundandtoldus.Youseethisgrassfieldinthecenteroftheschool?Hereiswheretheyholdtheir11ceremony仪式礼节.Theyjustsetuptentsandbenchesandhaveaverysimpleceremony.It's12!Whowouldthinkthemosttalentedstudentsjustgraduateonthegrass? I13somestudentsputablanketonthegrassandliedowntoreadabook.WhenIlistenedtothesoftsoundof14turningalongwiththesingingofthebirdsIfeltvery15.Therewasnocompetitivefeelingatall. Harvardhastheworld'sfirstcomputerinitssciencecentre16therearehundredsofhigh﹣endcomputerstoo.Itsreligionandtheliterature文学departmentsarealso17thebest.Itistheperfectmixoftraditionand18technology.ItmakesHarvardaveryattractiveplaceto19in. IhopeonedayI'll20mydreamschool﹣﹣﹣Harvard. 1.A.excited B.troubled C.shocked D.tired 2.A.more B.less C.little D.most 3.A.great B.solid C.noisy D.simple 4.A.still B.even C.ever D.yet 5.A.model B.way C.idea D.example 6.A.filled B.recovered C.surrounded D.floated 7.A.empty B.quiet C.free D.busy 8.A.once B.again C.only D.then 9.A.environment B.view C.atmosphere D.condition 10.A.guide B.partner C.visitor D.professor 11.A.celebration B.closing C.opening D.graduation 12.A.uninteresting B.unbelievable C.unbearable D.uncomfortable13.A.had B.saw C.felt D.imagined 14.A.books B.benches C.blankets D.pages 15.A.lucky B.calm C.nervous D.puzzled 16.A.but B.and C.though D.yet 17.A.among B.about C.to D.under 18.A.old B.new C.fast D.fresh 19.A.travel B.live C.study D.tour 20.A.serve B.visit C.find D.attend
下列有机物系统命名正确的是
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如图在菱形ABCD中已知AB＝4∠ABC＝60°∠EAF＝60°点E在CB的延长线上点F在DC的延长线上有下列结论①BE＝CF②∠EAB＝∠CEF③△ABE∽△EFC④若∠BAE＝15°则点F到BC的距离为2﹣2．则其中正确结论的个数是
10分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. WhennewscamethatIwasnotchosenasthememberofthevolleyballteamIwassuchfrustratedthatIalmostdecidedtogiveup.HowevermybestfriendMirandaanalyzedmyproblemspointedoutthatmylazinessandpoorpreparationledmyfailure.FromthenonIdevotedallmysparetimetopracticeplayingandconsultinghisteachersaboutskillseveryday.WhenanotherchancecameIhadgotfullyprepared.AsaresultofIwasselectedandbecameoneofthemostimportantplayerinourschoolteam.FromthisstoryIamdefiniteconvincedthatthebetterpreparedwearethemuchlikelyweareabletoachieveourgoals.
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10分 Flavoring Mostdrinksstatingthattheyarefruit﹣flavored水果味道的containnofruitatallwhilemostoftherestcontainonlyasmallquantityoffruitaccordingtoastudycarriedbytheBritishFoodCommission. Shoppersneedtocheckthelabels标签beforebuyingdrinksthoughsometimestheactualcontentcanbenon﹣existentsaidFoodCommissionspokespersonIanTokelove.Foodproductionishighlycompetitive.1Itwillincreaseprofitsandconsumerswon'talwaysrealizetheyarebeingtricked. Flavoringsarefocusedontheflavorsofnaturalfoodproductssuchasfruitsmeatsandvegetablesorcreatingflavorforfoodproductsthatdonothavethedesiredflavors.Researchersanalyzedthecontentsof28strawberry﹣flavoredproductssoldinstores.2Ofthe11productsthatdidcontainstrawberriesfiveofthemcontainedlessthanonepercentrealfruit.Inadditioneachjuiceboxcontainednearlyeightteaspoonsofsugar. 3Let'stakejamasanexample.Somestrawberry﹣flavoredjamwaslabeledascontainingnoartificialcolorsflavorsorsweetenersbutitcontainedabsolutelynostrawberriesatall. 4Consumershavetherightstoknowclearlyaboutwhattheyhavebought.UndercurrentUKlawfoodpackagesdonothavetodistinguishbetweennaturalandartificialflavoring.Describingaproductasstrawberryflavorandcoveringthesurfaceofthepacketwithpicturesofstrawberriesismisleading.5UnfortunatelyitisalsolegalandwidespreadTokelovesaid.It'stimetotakemeasurestoprotecttheconsumers'rights. A.Theproductswhichcontainrealfruitarepopularwithpeople. B.Evenproductsadvertisedasmorenaturaloftencontainednofruit. C.Theyfoundthatabout60vpercentofthemdidn'tcontainanyfruitatall. D.Ifcompaniescancuttheircostsbyusingflavoringtheyarelikelytodoso. E.Itisimportantandneessarytodemandasmallamountofflavoringintheproducts. F.Actuallytheproductcontainsjustatinypercentageofstrawberryorevennofruitatall. G.TheFoodCommissionsuggestedallflavorsusedinaproductshouldbelistedonthepackaging. 1. 2. 3. 4. 5.
如图1在平面直角坐标系中抛物线y＝﹣x2+bx+c经过点A﹣50和点B10． 1求抛物线的解析式及顶点D的坐标 2点P是抛物线上AD之间的一点过点P作PE⊥x轴于点EPG⊥y轴交抛物线于点G过点G作GF⊥x轴于点F当矩形PEFG的周长最大时求点P的横坐标 3如图2连接ADBD点M在线段AB上不与AB重合作∠DMN＝∠DBAMN交线段AD于点N是否存在这样点M使得△DMN为等腰三角形若存在求出AN的长若不存在请说明理由．
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8分Howfarwouldyoubewillingtogotosatisfyyourneedtoknow?Farenoughtofindoutyourpossibilityofdyingfromaterribledisease?Thesedaysthat'smorethananacademicquestionasTracySmithreportsinourCoverStory. Therearenowmorethanathousandgenetic基因的testsforeverythingfrombaldnesstobreastcancerandthelistisgrowing.Questionisdoyoureallywanttoknowwhatmighteventuallykillyou?ForinstanceNobelPrize﹣winningscientistJamesWatsononeofthefirstpeopletomaptheirentiregeneticmakeupissaidtohaveaskednottobetoldifhewereatahigherriskforAlzheimer老年痴呆症. IfItellyouthatyouhaveanincreasedriskofgettingaterriblediseasethatcouldweighonyourmindandmakeyouanxiousthroughwhichyouseetherestofyourlifeasyouwaitforthatdiseasetohityou.ItcouldreallymessyouupsaidDr.RobertGreenaHarvardgeneticist. EveryacheandpainSmithsuggestedcouldbeunderstoodasthebeginningoftheend.That'sright.IfyoueverworriedyouwereatriskforAlzheimer'sdiseasetheneverytimeyoucan'tfindyourcarintheparkinglotyouthinkthediseasehasstarted. Dr.Greenhasbeenthinkingaboutthisissueforyears.HeledastudyofpeoplewhowantedtoknowiftheywereatahighergeneticriskforAlzheimer's.Itwasthoughtthatpeoplewhogotbadnewswouldforlackofabettermedicaltermfreakout.ButGreenandhisteamfoundthattherewasnosignificantdifferencebetweenhowpeoplehandledgoodnewsandpossiblytheworstnewsoftheirlives.Infactmostpeoplethinktheycanhandleit.PeoplewhoaskfortheinformationusuallycanhandletheinformationgoodorbadsaidGreen. 1.Thefirstparagraphismeantto. A.asksomequestions B.introducethetopic C.satisfyreaders'curiosity D.describeanacademicfact 2.WhichofthefollowingistrueofJamesWatson? A.Heisstronglyinfavorofthepresentgenetictests. B.HeismorelikelytosufferfromAlzheimer'sdisease. C.Hebelievesgeneticmappingcanhelpcureanydisease. D.Hedoesn'twanttoknowhischanceofgettingadisease. 3.TheunderlinedpartfreakoutinParagraph5isclosestinmeaningto. A.breakdown B.dropout C.leaveoff D.turnaway 4.ThestudyledbyDr.Greenindicatesthatpeople. A.prefertoheargoodnews B.tendtofindoutthetruth C.canacceptsomebadnews D.havetherighttobeinformed
30分AtfirstpeopleintheUSthoughtEbola埃博拉wasonlyadiseaseaccompaniedwithfeverandfoundinAfricaatthebeginning.1thenamanfromwestAfricadiedfromEbolaatahospitalinDallasTexas.Andtwonurses2forhimbecameinfected感染withtheviruswhichmadetheUSgovernmentpublishnewguidelinesto3healthworkers. TopAmerican4haverepeatedlysaidthatmostpeoplehavelittlechanceofbeinginfected.Expertshave5thatEbolacanonlybespreadthroughinfectedperson'sbodyfluids﹣likeblood.Butit6thatmanyAmericansare7whattheyhaveheard. Arecentsurveyfoundmorethan80percentofAmericansbelievethatEbolacanbespreadinmany8includingairforcedthroughthenoseormouth.BesidestheHarvardSchoolofPublicHealth9thefindings.Thestudyalsoshowedthatmostadultsfeartherewillbean10ofEbolaintheUnitedStatessoon.11surveyfoundthatmorethan70percentofAmericanswouldsupportcallsto12traveltoandfromEbola﹣affectedpartsofAfrica. ThomasFriedenheadstheU.S.CentersforDiseaseControlandPrevention.Whenaskedwhether 13officialshadconsideredatravelbanMr.Friedenhad14tosay:Wewon'tbeabletochecktravelersfor15whentheyleaveorwhentheyarrive.Wewon'tbeableaswedo16totakeadetailedhistorytoseeiftheywere17whentheyarrive.Whenthey18wewouldn'tbeabletoimposequarantine强加隔离aswenowcaniftheyhavehigh﹣risktouch. LastweekPresidentBarackObamaurgedAmericansnotto19whathecalledpanicorfear.ThisweektheadministrationannouncedthatalltravelersreachingtheUnitedStatesfromsomeAfricannationsare20topassthroughoneoffiveairports. 1.A.Just B.Yet C.So D.Even 2.A.arranging B.caring C.searching D.standing 3.A.treat B.attend C.inspec tD.protect 4.A.policemen B.officers C.physicists D.doctors 5.A.stated B.suggested C.considered D.regretted 6.A.proves B.happens C.says D.appears 7.A.studying B.discussing C.questioning D.determining 8.A.ways B.areas C.organs D.countries 9.A.announced B.received C.realized D.rejected 10.A.increase B.income C.decrease D.outbreak 11.A.Theother B.Another C.Thesame D.One 12.A.forbid B.expect C.require D.allow 13.A.foreign B.royal C.African D.federal 14.A.that B.this C.nothing D.those 15.A.change B.money C.fever D.crime 16.A.immediately B.previously C.presently D.regularly 17.A.examined B.searched C.explored D.exposed 18.A.leave B.arrive C.live D.stay 19.A.lookforwardto B.payattentionto C.giveinto D.addupto 20.A.persuaded B.required C.advised D.guided
在我市“青山绿水”行动中某社区计划对面积为3600m2的区域进行绿化经投标由甲乙两个工程队来完成．已知甲队每天能完成绿化的面积是乙队每天能完成绿化面积的2倍如果两队各自独立完成面积为600m2区域的绿化时甲队比乙队少用6天． 1求甲乙两工程队每天各能完成多少面积的绿化 2若甲队每天绿化费用是1.2万元乙队每天绿化费用为0.5万元社区要使这次绿化的总费用不超过40万元则至少应安排乙工程队绿化多少天
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如图在岷江的右岸边有一高楼AB左岸边有一坡度i＝12的山坡CF点C与点B在同一水平面上CF与AB在同一平面内．某数学兴趣小组为了测量楼AB的高度在坡底C处测得楼顶A的仰角为45°然后沿坡面CF上行了20米到达点D处此时在D处测得楼顶A的仰角为30°求楼AB的高度．
8分Aslifeexpectancyincreasesnowadaystheaveragepersonliveswellbeyondtheageofretirement.Asaresulttheelderlymakeupanever﹣increasingpercentageofsocietywhichmakesitmoreimportantthaneverforarealefforttobemadeinimprovingthelivesofseniorcitizens. Onewaytodealwiththesituationwouldbetoensurethattheelderlyhaveenoughmoneyonwhichtolive.Obviouslywhenapersonstopsworkingtheystillrequireasourceofincometocovertheirbasicneedssuchasfoodaccommodationandheating.Aclearsolutiontotheproblemisforthegovernmenttomakesurethatthestatepensionisadequatefortheseneeds. Stepsshouldalsobetakentoovercomethehealthproblemstheelderlyface.Thegovernmentshouldalsoprovideaccesstothebesthealthcareavailablewhichmaynecessitatepayingforresidentialhomeswheretheelderlycanhaveround﹣the﹣clocknursingorattheveryleastprovidingmedicationfreeofchargetoallpeopleoveracertainage. Thelivesofoldpeoplecouldbeimprovedifattemptsweremadetoaddresstheproblemofsocialisolation.Ifweorganisedtripsfortheelderlytocommunitycentresvisitsfromsocialworkerstheirproblemoflonelinesscanbereducedalotwhichmarksthelivesofsomanyoldpeoplelivingaloneandfarfromtheirfamilies. Onefinalsuggestionwhichwouldhelpenormouslyistochangetheattitudeofthecommunitytowardsitsoldermemberswhoarealltoooftenseenasaburdenonsocietyanddismissedashavinglittletodowithmodernlife.Weneedtobetaughtfromanearlyagetorespecttheviewsofoldpeopleandappreciatetheirbroaderexperienceoflife.Thiswouldhelpsocietyasawholeandencourageappreciationoftherolethatoldpeoplecanstillplaytoday. 1.Whatdoesthepassagemainlytalkabout? A.Alltheelderlycanenjoyfreemedication. B.Thenursescantakegoodcareoftheelderly. C.Somesuggestionswouldbemadetoimprovethelivesoftheelderly. D.Thehealthcareavailabletotheelderlyisgood. 2.TheunderlinedwordaddressinParagraph4probablymeans. A.findout B.dealwith C.putdown D.pickup 3.Whatfactorsaffectedtheoldpeople'slife? a.thestatepension b.thebasicneeds c.theattitudeofthecommunity d.theexperienceoflife e.socialisolation f.medicalcare A.abcd B.bcde C.cdef D.acef 4.Accordingtothelastsuggestiontheoldpeople. A.shouldberespectedbyallofus B.havetogathermorelifeexperience C.mayberegardedasourheavyburden D.mustchangetheirattitudetothecommunity
6分EachmorningGrandpawasupearlysittingatthekitchentablereadinghisbook.Hisgrandsonwantedtobejustlikehimandtriedtocopyhimineverywayhecould.OnedaythegrandsonaskedGrandpaItrytoreadthebookjustlikeyoubutIdon'tunderstanditandIforgetwhatIunderstandassoonasIclosethebook.Whatgooddoesreadingthebookdo? ThegrandpaquietlyturnedfromputtingcoalinthestoveandrepliedTakethiscoalbasketdowntotheriverandbringmebackabasketofwater.Theboydidashewastoldbutallthewaterleakedoutbeforehegotbacktothehouse.ThegrandpalaughedandsaidYou'llhavetomovealittlefasternexttimeandsenthimbacktotheriverwiththebaskettotryagain. Thistimetheboyranfasterbutagainthebasketwasemptybeforehereturned.Outofbreathhetoldhisgrandpathatitwasimpossibletocarrywaterinabasketsohewenttogetabucketinstead.ThegrandpasaidIdon'twantabucketofwater;Iwantabasketofwater.You'rejustnottryinghardenough. Theboyagaindippedthebasketintotheriverandranhardbutwhenhereachedhisgrandpathebasketwasemptyagain.OutofbreathhesaidGrandpait'suseless!Soyouthinkitisuseless?thegrandpasaidLookatthebasket. Theboylookedatthebasketandforthefirsttimeherealizedthatthebasketwasdifferent.Ithadbeentransformedfromadirtyoldcoalbasketandwasnowclean.Grandsonthat'swhathappenswhenyoureadthebook.Youmightnotunderstandorremembereverythingbutwhenyoureadityou'llbechangedinsideandout. 1.Whatpuzzledthegrandsonmostwas. A.whetheritwasusefultoreadbooks B.whyheforgotwhathereadsoon C.whatkindofbookhecouldunderstand D.howhecouldreadbookslikehisgrandpa 2.WhydidGrandpaaskhisgrandsontofetchabasketofwater? A.Totrainhimtorunfaster. B.Tocleanthedirtybasketintheriver. C.Topunishhimfornotreadingcarefully. D.Togethimtorealizetheuseofreadingbooks. 3.Whatlessoncanwelearnfromthestory? A.Theoldarealwayswiserthantheyoung. B.Itisfoolishtocarrywaterwithabasket. C.Readingbookscanchangeapersongradually. D.Youcan'texpecttorememberwhateveryouread.
下列离子方程式书写正确的是
PM2.5是指大气中直径小于或等于2.5微米的颗粒物也叫可入肺颗粒物与肺癌哮喘等疾病的发生密切相关是灰霾天气的主要原因．它主要来自化石燃料的燃烧如机动车尾气燃煤等．下列与PM2.5相关的说法不正确的是
10分Justlikechildrenbabyanimalsspendcountlesshoursatplay.Afterstudyinganimalplayformanyyearsscientistsrecognizethatyounganimalplayispracticeforadultbehavior.Todaythisplayisroughlydividedintothefollowinggroups. Locomotorplayreferstothemovementsanimalscarryoutintheirplay.Runningleapingturningandkickingaresomeofthemostcommonexamplesoflocomotorplay.Anadultdeermayrunleapandtwisttoescapeitsattackers.Playmovementslikethesesurelymakeyounganimalsnimble.Somedaytheseskillsmighthelpsavetheirlives. Movingforwardslowlyattackingsuddenlyandbitingareexamplesofpredatoryplaythathelpyoungpredatorsprepareforalifeofrunningafterandtakingholdofotheranimals.Wildcatswolvesandbearsarepredators.Itisverycommontoseetheseyounganimalsplaythiskindofgameswhichsharpentheirskillsandteachthemabouttheirstrengthsandlimitations. Forchildrenplayingwithtoysisbothfunandeducational.Ithelpsimprovetheirhandandeyemovementsaswellasdevelophandskillstoaccomplishtasks.Itisthesamewithanimals.Youngchimpanzeesimprovetheirhandskillswhileplayingwithsticks.Birdsalsoplaywiththingsinwaysthatteach.Swallowsdropandrecoverfeathersinmidair.Divingsuddenlytocatchthefeathersisagoodpracticeforcatchingflyinginsects. Socialplayhelpsanimalslearnhowtobehavewhentheyrunintootheranimals.Anditteachesanimalsaboutcommunication.Ananimalgivessignalstoletanotheranimalknowitwantstoplay.Manyanimalsgivesignalsbyshowingaplayface.Insomewaysthisfaceislikeahumansmile;theanimalholdsitsmouthinarelaxedandopenmanner.Duringplay﹣fightssomeanimalsmaystepbackwardstosignalthattheyareplayingandnotactingseriously. Untilnowscientistshaveunderstoodplayfulactshelpprepareanimalsfortheirseriousadultsituations.Butthenumbersofplayfulspeciesandexamplesofanimalplayarevast.Thepurposeofanimalplaymayhavemeaningsscientistshavenotdiscoveredyet. 1.Themainpurposeofthetextisto. A.askustotakegoodcareofwildanimals B.encourageustolearnmoreaboutanimals C.entertainuswithinterestinganimalstories D.showussomethingaboutanimalbehavior 2.TheunderlinedwordnimbleinParagraph2canbestbereplacedby. A.cruel B.swift C.curious D.strong 3.Whichofthefollowingbelongstopredatoryplay? A.Adeerrunsleapsandturns. B.Achimpanzeeplayswithastick. C.Alionmovesslowlyandmakesanattacksuddenly. D.Adogholdsitsmouthinarelaxedandopenmanner. 4.BasedonParagraph5aplayfaceis. A.atypeofsignalbetweenanimals B.anameforakindofanimalplay C.anactivitythatinvolvesadultanimals D.anactionthatistaughttoanotheranimal 5.Whichofthefollowingshowsthestructureofthetext?
下列分离或提纯物质的方法正确的是
15分Agroupoffrogsweretravelingthroughthewoodsandtwoofthem1fallintoahole.Alltheotherfrogslookeddown.Whentheysawhowdeep2holewastheytoldthetwofrogsthattheywoulddiesoon. Atfirstbothofthetwofrogsdidn'tcaretheirwordsandtried3besttojumpoutofthehole.Theotherfrogskepttellingthemtostopbecausetheythoughttherewasnochance4jumpoutofsuchadeephole.Finallyoneofthetwofrogsbelievedthesewordsandgaveup.Hefelldownanddied. Theotherfrogcontinuedtojumpashardashecould.Onceagainthecrowdoffrogsshoutedathimtostopthepainandjustdie.Hejumpedeven5hardandfinallysucceeded.WhenhegotouttheotherfrogsaskedDidn'tyouhearus?6theirgreatsurprisethefrogturnedouttobedeaf.Hethoughttheywerehelpinghimallthetimenot7stophim. Thisstoryteachestwolessons:Thereispoweroflifeanddeathinthetongue.Well﹣meantwordscanhelppeopleintrouble.Butevilwordssometimescankillthem.Becarefulof8yousay. Rememberthepowerofwords.Anyonecanspeakwords9arelikelytomakepeoplegiveupindifficult10time. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.
设NA表示阿伏加德罗常数下列叙述中正确的是
6分Noonewouldmuchliketheideaofeating61poundsoftomatoesaday.Butiftheirgoodnesswasputintoaneasy﹣to﹣swallowpillthatyouweretoldmightpreventstrokes中风andheartattacksyouwouldprobablybeputtinginanordertomorrow. Researchersbelievetheymayhavecomeupwithjustthataftertrials.Thedailypillcontainsachemicalcalledlycopenewhichmakestomatoesredandisknowntobreakdownfatinthevessels血管.ACambridgeUniversitystudyfoundtakingthepillsimprovedbloodflowandtheliningofvesselsinpatientswithpre﹣existingheartconditions.Italsoincreasedtheflexibilityoftheirvesselsby50percent.Thescientistsbelieveitcouldlimitthedamagecausedbyheartdisease﹣responsiblefor180000deathsayear﹣andhelpcutthe49000deathsayearfromstrokes.Theyalsohopeitcouldbenefitthosewitharthritis关节炎diabetes糖尿病andevenslowtheprogressofcancer. Eachpillisequaltoeatingaround61poundsofripetomatoes.StudieshaveshowneatingaMediterranean﹣styledietrichintomatoesfishvegetablesnutsandoliveoilcansignificantlyreducecholesterol胆固醇andhelppreventcardiovasculardisease. Preliminaryresultsfromatwo﹣monthtrialinwhichthepillwasgivento36heartdiseasepatientsand36healthyvolunteerswithanaverageageof67werepresentedatameetingoftheAmericanHeartAssociation.Itwasshowntoimprovethefunctionoftheendothelium﹣thelayerofcellsliningbloodvessels.Italsoimprovedtheirsensitivitytonitricoxidethegaswhichcausestheenlargementofthevesselsinresponsetoexercise. IanWilkinsonheadofCambridgeUniversity'sclinicaltrialsunitsaidTheseresultsarepotentiallyverysignificantanditmeetsthegoalbutweneedmoretrialstoseeiftheytranslateintofewerheartattacksandstrokes. Furtherstudiesareplannedwithresearchershopingitcouldofferachoiceforheartdiseasesuffererswhocannottakethecholesterol﹣lowingdrugs. MikeKnaptonheadoftheBritishHeartFoundationsaidAlthoughthisshowedlycopeneimprovedbloodflowinpeoplewithheartdiseasethat'salongwayfromdemonstratingthattakingitcouldimproveoutcomesforpeoplewithheartdisease.Thebestwaytogetthebenefitsofagooddietistoeatplentyoffreshfruitandvegetables. 1.WhatcanweinferfromParagraph1? A.Wecaneattoomuchtomatofood. B.Tomatoesarehelpfultostrokesandheartattacks. C.Tomatoeswilllosehealthyelementswereputintopills. D.Wehadbetternoteattomatoes. 2.Wecanlearnfromthepassagethatthepills. A.areattheexperimentstage B.cancureallthedisease C.arewidelyusedamongpatients D.costpatientssolittlemoney 3.WhatWasIanWilkinson'sopiniononthetrial? A.Disappointing. B.Surprising. C.Satisfactory. D.Terrible.
下列关于合成材料的说法中不正确的是
6分NingZetaohasbecomeChina'snewswimmingstarduetohisamazingperformanceatthe2014AsianGamesinIncheon仁川SouthKorea.Withalreadytwogoldmedalsinhandthe21﹣year﹣oldclocked47.70secondsinthe100mfreestylesettinganewAsianrecord.ThisresulthasbeenrecognizedbyFINAastheworld'sthirdbesttimethisyearfastenoughtohavewonagoldmedalinlastyear'sBarcelonaWorldChampionships.ItismyfirstinternationaleventsaidNingwholaterwonafourthgoldmedalinIncheon.Iamhappythatmyresultsareprettyclosetomypersonalbest. BorninthecentralChinesecityofZhengzhouNingenteredthelocalteamattheageof11andjoinedthenavyteamin2007.Hefirstcaughtpeople'sattentionin2009whenhefinishedeighthinthe200mindividualmedley混合泳attheNationalGames. NeverthelessNingsufferedfromboneinfectioninbothkneesforalongtimewhichmadehimunabletotrainhardonhiskicks.Healsohadanindigestionproblemandhadtoeatsoftfoodwhichiseasytodigest.Hispoorstomachevenmadeitimpossibleforhimtocompleteweek﹣longfulltimetraining.Buttheyoungswimmernevergivesup.HisidolisthegreatRussianswimmerAlexanderPopovwhocontinuedtowinOlympicgoldmedalsafterhewasstabbed刺伤onastreet.NingsaidHewasarealfighterandIneedtolearnfromhim. TakenbettercareofbycoachesanddoctorsNingcannowtrainasnormallyasothers.Andthatiswhyhecangettoday'sachievements.ThegoldmedalsattheAsianGamesalsoboostedtheconfidenceofthenewswimmingstarwhohopestoenterthenationalteamandcompeteforChinainmoreinternationalevents.Chinesemaleswimmershaveneverbeenplacedamongtopeightintheshort﹣distancefreestylehesaid.IhopeIcandoitjustlikewhatSunYangdidinthemid﹣longdistancefreestyle. 1.Thebesttitlecouldbe. A.NingZetaoaworldfamousswimmer B.NingZetaoapromisingrisingstar C.NingZetaoastrong﹣willedsoldier D.NingZetaoaworldgoldmedalist 2.Wecanlearnfromthepassagethat. A.theresultsNinggotinIncheonarehisbest B.Ningisgoodatboth100mand200mfreestyle C.NingbrokeanAsianrecordatthe2014AsianGames D.Ninghasalreadygot5goldmedalsintheinternationalevent 3.Itcanbeinferredfromthepassagethat. A.somehealthproblemshavelittleeffectonNing'straining B.beingwellcaredofisthemainreasonforNing'sachievements C.theChineseswimmershavenevergotintothetopeighthintheworldevent D.goldmedalistasNingisheisnotyetamemberofNationalSwimmingTeam
25分假定你是希望中学学生李华得知2017年香港大学要在大陆进行自主招生的消息后有意向香港大学申请参加自主招生考试请用英语写一封自荐信主要包括:1.个人信息2.性格爱好与特长3.学习情况注意:1.词数100左右;2.信的开头已为你写好不计入总词数;3.可根据内容要点适当增加细节以使行文连贯.4.参考词汇:自主招生independentrecruitmentDearSirMynameisLiHuafromHopeHighSchool.YoursLiHua.
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