【Youhavebeenbadlyinjuredinacaraccident.Itisnecessarytogiveyouabloodtransfusion(输血)becauseyoulostagreatdealofbloodintheaccident.However,specialcaremustbetakeninselectingnewbloodforyou.Ifthebloodistoodi】

　　Youhavebeenbadlyinjuredinacaraccident.Itisnecessarytogiveyouabloodtransfusion(输血)becauseyoulostagreatdealofbloodintheaccident.However,specialcaremustbetakeninselectingnewbloodforyou.Ifthebloodistoodifferentfromyourown,thetransfusioncouldkillyou.

　　Therearefourbasictypesofblood:A,B,ABandO.Asimpletestcanshowaperson’sblood

　　type.Everybodyisbornwithoneofthesefourtypesofblood.Bloodtype,likehaircolorandheight,isreceivedfromparents.

　　Becauseofsubstances(物质)containedineachtype,thefourgroupsmustbetransfusedcarefully.Basically,AandBcannotbemixed.AandBcannotreceiveAB,butABmayreceiveAorB.Ocanbegiventoanyothergroup,hence,itisoftencalledtheuniversaldonor(万能输血者).Fortheoppositereason,ABissometimescalledtheuniversalrecipient.However,becausesomanyreactionscanhappenintransfusions,patientsusuallyreceiveonlysaltorplasma(血浆)untiltheirbloodcanbematchedasexactlyaspossibleinthebloodbankofahospital.Inthisway,itispossibletokeepawayfromanybadreactionstothetransfusions.

　　Thereisarelationshipbetweenyourbloodtypeandyournationality.AmongEuropeansandpeopleofEuropeanancestry(祖先),about42%havetypeAwhile45%havetypeO.TherarestistypeAB.

　　Otherraceshavedifferentpercentages(比率).Forexample,someAmericanIndiangroupshavenearly100%oftypeO.

　　31.Agoodtitleforthispassageis_____.

　　A.GettingBloodandPlasma

　　B.SpecialBloodColors

　　C.HumanBloodTypes

　　D.TheRelationshipBetweenYourBloodTypeandYourNationality

　　32.Theword“hence”inthethirdlineofthethirdparagraphmeans_______.

　　A.alwaysB.oftenC.sometimesD.therefore

　　33.TheauthorsuggeststhatthethirdmostcommonbloodtypeamongEuropeansis_______.

　　A.AB.BC.ABD.O

　　34.HowmanytypesofbloodcanapersonreceiveifhisbloodtypeisAB?

　　A.Four.B.Three.C.Two.D.One.

　　35.Ifyouneedatransfusion,thebestandsafebloodforyouis______.

　　A.typeOB.typeA

　　C.typeABD.exactlythesametypeasyours