C

                    ★★★★☆ 

   Areyouatleast17yearsold?Doyouweighmorethan110pounds?Doyouconsider yourselffairlyhealthy?

   Ifyouansweredyestoallofthesequestionsyoushouldbedonating(捐赠)bloodeverytwomonths.InmysurveyofmyschoolmatesIfoundthatonly50percentofthemhaveeverdonatedbloodandthatonlyI outof13ofthemdonateregularly.Thelack(缺少)ofblooddonorsisaseriousproblemthatrequiresimmediateaction.

   AccordingtotheAmericanRedCrossWebpagesintheUnitedStatesalonesomeonereceivesatransfusion(输血)onceeverythreeseconds.Peoplewhobenefitfromdonationsincludecancerpatientsaswellasbabies.Theneedforbloodnevertakesavacationandneithershoulddonors.

   LetmetellyouaboutBrookeathree-year-oldgirlwithcancer.Brookehasspentabouthalfofherlifeinthehospitalreceivingofthetotalamounttocontinuehertreatment.Ifshedoesnt  receivethisbloodshewillnotlivetoIstartkindergarten.

   ExampleslikeBrookesarebecomingalltoocommonthesedayswithonly1in20 Americansjdonatingbloodandthisnumberkeepsdropping：eachyear.Thesefactsareextremelyworryingconsideringthatnearlyhalfofusherewillneedbloodsometimeinourlives.

   YoucannowseetheseriousnessoftheIproblemwiththelackofblooddonationsFortunatelyitisaproblemthatcanbeeasilyIsolved.Eachandeveryoneofyoucanbepartof thesolution.AllyouhavetodoisgotothenearestIRedCrossanddonateyourblood.

28.HowdoestheauthorexplaintheproblemmentionedinParagraph2?

   A.Byansweringquestions.!

   B.Bymakingcomparisons.

   C.Bypresentingresearchfindings.

   D.Bydescribinghisownexperiences.

29.WhatqanwelearnfromtheAmericanRed 

CrossWebpages? 

   A.Thesufferingofpatients.

   B.Thestrongneedforblood.

   C.TheeffortsoftheRedCross. 

   D.Thebenefitsoftakingvacations.

30.Thethree-year-oldgirlBrooke.

   A.doesntgetfairtreatmentinthehospital 

   B.willneedanother250unitsofblood

   C.staysalivebyrecei