下列关于参照完整性约束的叙述中,哪些是正确的?

A、参照完整性约束是一种关系模型完整性约束
B、在关系模型中实体及实体间的联系都是用关系来描述的于是就自然存在着关系与关
C、两个或两个以上的关系间可以存在参照关系
D、同一个关系的属性间不可能存在参照关系
E、参照关系中每个元组在外码属性上的取值只能等于所对应的被参照关系中某个元组的主码值
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正确答案:

ABC

答案解析:

暂无解析

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PartIIICloze

Directions:Therearetwentyblanksinthefollowingpassage.Foreachblanktherearefourchoices.ChoosetheonethatbestfitsintothepassageandthenmarksyouranswerontheAnswerSheet.

In1982,MarkThatcher,thesonofMrs.Thatcherwasreported61intheSaharaDesertwhilecompetingintheGrandPrixmotorracefromParistoDakar.Thissadnews,so62,shooktheusuallycalmandunperturbedseasonedpolitician63herbalance.Thoughshedidherbesttopretendasif64hadhappenedandmadeherpublicappearancesasusual,peoplecouldnot65tonoticethatshewasnolongertheold66primeministerwhoalwayshadeverything67control.68shehadbecomeaverysadmotherwhowasunabletorecoverfromhershock.

Oneday,whenshewastospeakataluncheonparty,areportercaughther69herguardby70upthesubjectofhermissingsonagain.Shewastotallymentally71forthequestionandlostherselfcontrol.Tearswererollingdownhereyesasshesobbinglytoldthereporterthatthere72stillnonewsofMarkandthatshewasveryworriedabouthim.Shesaidthatallthecountries73hadpromisedtodotheirbesttohelpherfindherson.74thatshebrokedowncompletelyandsobbedsilentlyforquiteawhile.Graduallyshe75downandstartedtospeakas76.itwasaverymovingscenewhich77anewsideofMrs.Thatcher’scharacterthepublicdonotusuallysee,78peoplebegantotalkabouttheIronWoman’smaternallove,asentimentthatis79toallhumankind.

LaterMarkreturned80andsoundtohismother’sside,good-humoredandallsmilesasusual,asifnothingunusualhadeverhappened.TheIronWoman,however,brokedownagainaswassobbingforthesecondtime.

61.A.missingB.missedC.wantingD.wanted

62.A.expectedB.expectingC.unexpectedD.unexpecting

63.A.withB.onC.outD.off

64.A.somethingB.anythingC.nothingD.everything

65.A.missB.failC.pretendD.expect

66.A.reassuredB.self-assuredC.assuringD.self-assuring

67.A.forB.beneathC.belowD.under

68.A.InsteadB.howeverC.ThereforeD.So

69.A.intoB.outofC.onD.off

70.A.puttingB.bringingC.takingD.giving

71.A.readyB.preparedC.unpreparedD.unexpected

72.A.wasB.wereC.shouldbeD.wouldbe

73.A.concerningB.concernedC.worryingD.worried

74.A.AtB.BeforeC.AfterD.With

75.A.satB.brokeC.calmedD.became

76.A.plannedB.planningC.plansD.aplan

77.A.explainedB.exposedC.excludedD.exclaimed

78.A.howeverB.insteadC.soD.but

79.A.universalB.uniqueC.singleD.strange

80.A.safeB.safelyC.sightD.hearing

关于体格检查内容不包括的是

A、精神状态
B、头部
C、颈部
D、背部皮肤
E、腹部和上肢

关于催产素静脉静滴,下列哪项是正确

A、用于低张型宫缩乏力以加强宫缩
B、用于轻度胎儿窘迫,需加快结束分娩
C、难产时,不宜使用
D、足月引产时,需大剂量方有效
E、用于多产妇引产更敏感

PartIVTranslation

Asthesourceofaluminumisalmostinexhaustible,wecanexpectthatmoreandmoreuseswillbefoundforthisversatilemetal.(PassageTwo)

PartIVTranslation

Thesubjectsinhisexperimentwere75collegestudents.TheyrepresentedalllevelsofabilityinEnglish:beginning,intermediate,andnative-speakingstudents.(PassageTwo)

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