大学英语六级考试模拟试卷十七（带答案）

大学英语六级考试模拟试卷十七

（总分：710.00,做题时■间：130分钟）

PartIWriting（总题数：1,分数；0,00）

LDirections:Forthispart,youareallowed30minutestowriteashortessayto

expressyourviewsonthephenomenonofkeepingpetsindormitories.Youshould

writeatleast160wordsbutnomorethan200words.

（分数：106.50）

正确答案：（［范文］

PetsShouldnotBeKeptinDormitories

Itisfrequentlyreportedthatsomecollegestudentskeeppetsintheir

dormitories.Attitudestowardthisphenomenonvaryfrompersontoperson.Some

peoplethinkit'snotabigdeal,whileothersmaintainthat'sunacceptable.Asforme,I

supportthelatter.

Firstofall,keepingpetsmightimperilourhealthbecausepetsmaycarrysome

potentialbacteriawhichcanleadtoseriousdiseases.What'smore,somepetssuchas

catsmayattackpeoplealthoughtheyaredocilemostofthetime.Secondly,thereisno

doubtthatitconsumesalotoftimeandmoneyforthekeepertoraiseapet.Thirdly,it

isforbiddentokeeppetsinmostcolleges.Onbalance,weshouldobeytheregulations

andpaymoreattentiontoourstudy.

Toconclude,itisinappropriateforstudentstokeeppetsindormitories.Ifyou

areananimallover,youcandosomethingforthestraycatsordogswhicharevery

easytofindoncampus,）

解析：

PartIIListeningComprehensionf总题数：0,分数］0,00）

SectionA（总题数：8,分数：0.00）

,Questions1to4arebasedontheconversationyouhavejustheard,

L（分数：28.40）

A.Hehasopenedanewaccount,

B.Something'swrongwithhisaccount.J

C.Hebegantopayacarloan.

D.Hehadtodealwithafinancialcrisis.

解析：［听力原文］

M:Idon'tunderstandit.IgotanoticefromthebankthatIhadtworubber

checks.I'veneverhadanoverdraftbefore,

W:Thatdoesn'tsoundlikeyou.You'realwayssocarefulwithyourmoney.

M:Iam!Idon'tunderstandwhathappened.

W：Letmetakealookatyourbankstatement.OK,hereareyourdepositsand

withdrawalsfromlastmonth.Doyouknowthatyourbankchargesyouafeejustto

haveacheckingaccount?Itlookslikeyoualsohaveaminimumbalancerequirement.

Ifyoufallbelowthat,yougetchargedafee.

M:Idon'tknowthat.

W:Ifit'slikemycheckingaccount,youcanavoidthatbygettingadirectdeposit

foryourpaycheck*Doyoualsoknowthatyougetchargedeverytimeyouuseyour

ATMcardtomakeapurchase?

M:Idon'tknowthat!Itisallratherunbelievable.

W:Well,that'swhathappened.Yourbankischargingyoufeesforallthose

thingsandafterthosefeeswerededucted,youwereleftwithlessmoneyinyour

accountthanyouthought.

M:That'stoomuch!Howcouldtheydothat?

W:Theycountonyounotreadingthetermsandconditionsandnotlooking

closelyatyourstatements,

M:I'vehadit!I'mmovingbanks.

Whathappenedtotheman?

,Questions5to8arebasedontheconversationyouhavejustheard.

5.（分数：28.40）

A.Thebuildingwiththelogshape.

B.Thetraditionallogcabin.J

C.Theseniorhomeswithlogs.

D.Theblockingbeamsandwalls,

解析：［听力原文］

M:Asweprobablyknow,logstructuresaregainingpopularity.Wecanfind

thosestructuresaroundthecountryside.

W:Actually,logstructuresarenolongerjustthesimplecountryhomesthatwe

thinkofasthetraditionallogcabin.Someseniorhomesnowincorporatenaturalround

logsinblockingbeamsandwalls.

M:Peopleseemtothinkthattheroundlogsgivetheirhomesapleasantwarm

atmosphere.

W:Yes,andevenpeoplewhowanttobuildatraditionallogcabinontheirown

canbuyequipmentwithprecutlogsthatfittogetherlikepiecesofpuzzle.

M:Beforeshowingussomeslidesofmodernloghouses,wouldyouliketogive

usalittlehistoricalbackgroundonthesubject?

W:Ofcourse,Iwouldliketo.Logcabinswerefirstbuiltinthelate1600salong

theDelawareRiverValley.TheEuropeanimmigrantswhosettledtherebrought

centuries'oldtraditionsofworkingwithlogs,

M:Inthatheavilywoodedarealogswerethematerialinhand.

W:Logcabinswerethemostpopularintheearly1800swiththesettlerswho

weremovingwest.Theyprovidedtheanswertothepioneers'needforasaleand

slidingboardsforwindows.

M:Actually,theselogbuildingscanmeetthedemandsofdifferentkindsof

people.

W:Well,thelogbuildingsthathaveprobablymostinfluenceonmodern

architectsarethoseofthemountainretreatsofwealthyNewYorkers.Thesecountry

houseswhichwerepopularintheearly1900srepresentwhat'sknownasthemodern

style.

M:Thankyouforyourdescription.Nowlet'slookatthoseslides.

Whatdidthelogstructuresrefertooriginally?

SectionB（总题数：7,分数:0,0。）

.Questions9to12arebasedonthepassageyouhavejustheard.

1.（分数：28.40）

A.Stoptobuyanumbrella.

B.Runquicklythanusual.

C.Findshelterfromrain.

D.Walkatnormalspeed.J

解析：【听力原文］

Whencaughtinpouringrainwithoutanumbrella,mostpeoplepickuptheir

pace.Butanoldtaleadvisesthatapersonwhorunsintheraingetswetterthanone

whowalks.Itsoundsreasonablethatwhensomeonerunsupanddown,thebodyis

exposedtomoredropsofwaterButseveralstudieshaveputthissayingtothetestand

founditisnottrue.Onesuchtestwascarriedoutin1987andwaspublishedin

EuropeanJournalofPhysicsmagazine.TheItalianphysicistwhodidtheexperiment

saidthatifthedistanceisshortenough,runninggetsapersonlesswetthanwalking.

Butrunningonlykeepsyouabout10percentdrierThatistosay,runningisn'tworth

theeffort.PerhapsthefinalwordcamefromtwoAmericanscientistsattheNational

ClimaticDataCenterrecently.Theythoughtthatearlierstudiesoverestimatedthe

averagewalkingpace.So,theydidamuchmorecarefulexperimentthananyofthe

previousones.Theynoticedthatthedirectionofthewindreallymatterstotheresults

oftheexperiment.Theyalsofoundthatrunnersliketoleanforward,hidingthefront

oftheirbodiesfromrain,butexposingtheback.Overadistanceof100meters,they

foundthatrunninginheavyrainkeptthemdrierbyasmuchas40percent.Thebottom

lineisrunningintherainprobablykeepsyoudrierthanwalking.Butdorememberto

takeanumbrellawithyou!Forlongdistances,withoutanumbrella,theresultsarethe

same,nomatteryourunorwalk.

Whatshouldpeopledowhencaughtintherainaccordingtotheoldtale?

,Questions13to15arebasedonthepassageyouhavejustheard,

5.（分数：2130）

AJtstillcanbeused.J

BJtwillbreakdown.

CJtshouldbethrownaway.

D.ltwillbecomebent.

解析：［听力原文］

Supposesomeoneinventedagiftcardsoversatile（多功能的）thatitcouldbe

usedalmostanywheretobuyalmostanything.Thisgiftcardwouldbegoodforever

andwouldbeacceptedinmanyforeigncountries.Youcouldbenditinhalf——oreven

leaveitinthepocketofyourtrunks（男式游泳裤）whenyouwentforaswimandit

wouldstillworkfine.Waitaminute.Somebodyalreadyinventedthatgo-anywheregift

card.It'scalledcash.Cashhashugeadvantagesovergiftcards.There'sbeenabig

troubleaboutgiftcardfees,soCongresseventuallysteppedintolimitthem.Anda

sizablechunkofgiftcardvalue——estimatesrangebetween5%and10%—nevergets

fullyused.Thesearen'tissuesthatcomewithcash.Sowhyhavegiftcardsgrownin

popularitywhenwealreadyhavesomethingbettersittinginourwallets?Theanswer

isacombinationofconsumerpsychologyandopportunisticretailersandcardissuers.

Consumersseegivingcashassilly,andretailershavetakenadvantageofthattopush

giftcards.Moststorecardsdon'thavefeesanymore.Theyhaveadifferentproblem.

You'recommittedtousethecardatadesignatedstore.AndanewNationalRetail

Federationsurveyfindsthatshoppersexpecttospendabitlessonholidaygiftcards

thisyear.

Whatwillhappenifthemultifunctiongiftcardfallsintowater?

SectionC（总题数:10,分数：0.00）

,Questions16to19arebasedontherecordingyouhavejustheard,

L（分数；56.80）

A.Thefactorsthataffectourdecision-making.

B,Somewaystodevelopourskillsandtalents,J

C,Someguidelinesonhuntingpart-timejobs.

D.Theadviceonhowtobeversatile.

解析：［听力原文］

Howevergiftedsomeonemaybe,heorshestillhadtodevelopvarioustalents

toachievealoftyprofessionalposition.Andthat*sgoodnewsfortherestofus.Each

oneofushasourownskillsandtalents,andwetoocandevelopthemandpropel

ourselvesintopositionsofinfluence.Herearesomewaystoenhancethosetalents.

First,developyourcriticaldecision-makingskills.Decision-makingisatop

leadershipcompetencybecauseitpopsupeverywhere,fromthesimplechoiceof

wheretoholdastaffmeetingtothestrategicoptionofwheretospendmarketing

dollars.Thesedecisionsimpactthepeopleinthenextcubicle（小隔间）,buttheymay

alsoaffectasubsidiary（了公司）halfwayacrosstheglobeoranentirecountry.

Decisivenessisnotatraitwe'rebornwith-it'saskillthatcanbelearned.To

masterit,analyzeyourprocessofcriticaldecision-makingtospotweaklinksinyour

reasoningandtorecognizeunconsciousbiasesfororagainstsomethingorsomeone.

Whilewecan'tcontroloutcomes,wecanshapetheprocessthatsetstheminmotion.

Second,learntomakeasolidargument.

YoumayneveraddresstheUnitedNationsSecurityCouncilortestifybefore

Congress,buteveryoneshouldbeabletoputtogetheracoherentargument.Thatskill

iscriticallyandfrequentlyuseful-----inhigh-stakesconversations,presentations,

question-and-answersessionsandinotherdiscussionswithdecision-makersoranyone

elsewhorepresentsacertainviewpointorasksyoutoexplainyours.

Toarguemeanstogivereasons.Itmeansdefendingandpromotingyourchoices

againstthecontraryargumentsofequallyadeptinfluencers.Takewhatyou'velearned

inschoolandbuildonthatbasewithprivateinstructionanddirectedreadingonthe

relevantsubject.You'llfindthatyourabilitytothinkcriticallyandanalyzeothers'

argumentswilldramaticallyincreaseyourinfluenceontheirchoices.

Third,becomeastoryteller.

Storytellinghasbeenapremier（首要的）toolininfluencingpeopleacross

culturesanderas.Influencerstellstoriesforstrategicpurposes.Frommotivating

peopletoact,toteaching,toreducingresistanceandchangingminds,awell-told

narrativeisaformidableforce,oftenfarmorepowerfulthanthemererecitationof

complexfinancialortechnicalfacts.Numbersandfiguresareimportant,butwhenit

comestoshowingtheirrelationshiptoanyissue,largeorsmall,astrategicnarrative

wrappedaroundthedigitswilldeliverthemessagebetterandmorememorablythan

anythingelse.

Afteryoumasterthedata,askyourself:Isthereawaytoputahumanfaceon

mymessage?Aretherereal-lifeexamplesthatwillhelpmemakemypointinaway

otherscanrelateto?

Whatdoesthespeakermainlytalkabout?

.Questions20to22arebasedontherecordingyouhavejustheard.

5.（分数；42,60）

A.Parentsneverasktheirchildrenforadvice.

B.Parentsalwaysgivetheirchildrenconstructiveadvice.

C.Mostteenagersseldomfollowtheirparents'advice.J

D.Mostteenagershavegotgoodadvicefromtheirparents.

解析：［听力原文］

Today,Iamgoingtotalktoyousomethingaboutadvice.Adviceisafunnything.

Somepeopleseemtohaveaconstantsurplusofit,andofferitnonstoptothose

aroundthem,evenwhenitisunsolicitedorunwelcome.

Othersareonthereceivingendoflotsofadvicefromothers,buttheyrarely

takeanyofit.

Averycommonexampleofnaskhole"behavioroccursintheteenageyears.

Teenagers'parentscanbecomeconstantbroadcastersofadvice,andtheyoungerfolks

developevermoresophisticatedskillsforappearingtolistenwhileactuallyturning

downthevolumeoftheincomingmessagestonearlyzero.Inmostcases,teenagers

rarelyfollowtheirparents'advice.

I'veheardexperiencedparentswhosechildrenarenowfullygrown,saythat

evenwhenteenagersseemtobeinatunnelwhichparentalcommunicationsignals

seemunabletopenetrate,parentsshouldstillkeeponofferingtheirunsolicited

wisdom,perspectives,andadvice.Thetheorygoes,thatevenintheabsenceof

acknowledgement,letaloneagreement,acertaindegreeofthemessagestillseeps

throughinthelongrun.

Ontheotherhand,likealladvice,thisdependsonthetoneandmodeofdelivery.

Thereisafinelinebetweenadvice?forexample,andnagging.Somepeopletendto

takegoodadviceanddeliveritinsuchawaythatitsoundslike,andisheardas?nagging.

Advicetransformedintonaggingisusuallyexcessivelyrepetitive,criticalratherthan

constructiveintone,sometimescondescending（屈尊）'andusuallyaone-waystreet.

Youmaygiveyouradvicewithoutaninvitationforfeedbackorresponsesuchas"What

doyouthink?11

Theteenager-parentcontextisasomewhatspecialone,butgivingandreceiving

advicepervadesourprofessionalandpersonallives.Ifyouthinkaboutyourfriendsand

associates,theyprobablyincludepeoplewhoeithergivetoomuchadvice,includingon

subjectswheretheirexpertiseisdoubtful,orofferadviceinanunhelpfultone,e.g.

bossyorcondescending.You'llprobablyalsofindfriendsandassociateswhoignored

someverygoodadviceandgotthemselvesintoaverydifficultsituationasaresult.It

isnotinstinctiveforustoaskforadvice.Therearefaceissuesinvolved,andpotential

embarrassment,especiallyintheworkplace.Ontheotherhand,wedenyourselvesa

lotoflearningopportunitiesandweareafraidtoaskadvicefromthosewithricher

experiencethanwehave.

Whatcanbelearnedaboutteenagersandtheirparents?

,Questions23to25arebasedontherecordingyouhavejustheard.

8.(分数：42.60)

AJheyaremoreimportantthanprofessionalskills.

BTheyimproveyourpersonalrelationship,

CTheymakeyouinvaluabletoemployers.J

D.Theyhelplittlewithtechnologyarea.

解析：［听力原文］

Here'saquestionforyou.Whataretheliberalarts?Theliberalartsrefertoa

widerangeofacademicsubjectsthatcanpreparestudentsforavarietyofoccupations.

Collegemajorsthatfallunderthiscategorydonottypicallytrainstudentsfor

anyonecareer.Itincludesbroadareasofstudysuchasthehumanities,socialsciences,

naturalsciencesandmathematics.Thehumanitiesincludesubjectssuchasdrama,

music,danceandlanguage.Sociology,psychology,geographyandeconomicsareall

socialsciences.Biologyandphysicsaretwoexamplesofnaturalsciences.

Regardlessofthecareeryouchoose,certainqualitiescalledsoftskillswillmake

youinvaluabletoemployersandarevitaltoyoursuccessinmanyoccupationsincluding

thoseintechnology.Theyincludecriticalthinking,problemsolving,creativityand

innovation,researchskills,writingandoralcommunication,interpersonalskillsandthe

abilitytolearn.

Youmayalreadyhavesomeoftheseabilities,butyoumustfindawaytoacquire

thoseyoudon't.Thebestwaytodothatisthroughliberalartseducation.Regardless

ofyourmajor,makeroominyourscheduleforclassesinliterature,history,sociology

andpsychology.

Thesecondquestionis:shouldyoumajorinliberalarts?

ThereisroomforbothSTEM(Science,Technology,EngineeringandMath)and

liberalartsintheeducationofourfutureworkforce.Studentsshouldbeexposedto

bothareasofstudy,butwemustalsorealizethatthereisasuitablecareerforeveryone.

Youmayfindthatacareerthatemphasizestheliberalartsisabetterfitforyouwhile

yourbestfriendmayfindsuccessinaSTEMoccupation.

Ifyouwanttopursueacareerthatrequiresyoutogetanundergraduatedegree

inoneofthesubjectsthatfallsunderthiscategory,youshouldcertainlydothat.Ifyou

willultimatelyneedamaster'sdegreeforyourchosenoccupation,youmayhavesome

flexibilityregardingyourundergraduatemajor.Choosingaliberalarts

majorwillallowyoutonotonlyamassthesoftskillsthatwillfollowyouthrough

graduateschoolandyourfuturecareer,butitwillalsoexposeyoutoknowledgeina

widerangeofsubjects.

Whatcanbelearnedaboutsoftskills?

PartIIIReadingComprehension（总题数：0,分数：0.00）

SectionA（总题数：10,分数：0.00）

.Facebookiscrackingdownoncryptocurrencies（力廿密数字货币）byusingone

ofitsmostpowerfultools:accesstoitsmassiveadvertisingmegaphone（宣传）.The

socialnetworkinggiantsaidonTuesdaythatitwillnot1adsforfinancialproductsthat

"arefrequentlyassociatedwithmisleadingordeceptivepromotionalpractices,"

specifically2currenciesand"initialcoinofferings,"afundraising（筹款的）tacticthat

newcryptocurrenciesusetoattractfreshinvestors."Wewantpeopletocontinueto

discoverandlearnaboutnewproductsandservicesthroughFacebookadswithoutfear

of3ordeception,"wroteRobLeathern,aproductmanagementdirectoratFacebook,

inablogpost.

Thespectacular4inpriceslastyearofbitcoinandmanyalternative

cryptocurrencieshassparkedasurgeofinterestamonginvestorsandcompaniesofall

kinds.Therampancyhasledtoschemesthat,insomecase,promisetriple-digitreturns

andhave5theinvestigationoftheSecuritiesandExchangeCommission（SEC）.

"Marketprofessionals,especiallygatekeepers,needtoact6andholdthemselvesto

highstandards,"SECChairmanJayClaytonsaidinrecentspeech."Tobefrank,from

whatIhaveseenrecently,7intheinitialcoinofferingspace,theycandobetter."

Facebookprovidedanumberofexamplestoillustrateitsnewpolicy,suchas

ad8thatadvisesuserstoconverttheirretirementfundsintobitcoinorpromotionsfor

"no-risk"cryptocurrencies.

TheannouncementcomesweeksafterFacebookchiefexecutiveMark

Zuckerbergacknowledgedthepotentialofcryptocurrenciesto9powerawayfrom

"centralizedsystems.""Theycomewiththeriskofbeinghardertocontrol,"Zuckerberg

saidinaFacebookpost."I'minterestedtogodeeperandstudythepositiveand

negativeaspectsofthesetechnologies,andhowbesttousethemin

10

A.attractedF.eliminateK.scams

B.authorizeG.essentialL.services

C.captureH.increaseM.simultaneously

D.copy1.particularlyN.strategy

E.displayJ.responsibly0.virtual（分数：35.50）

1.（分数：3.55）

填空项1:（正确答案：E）

解析：动词辨析题。由结构willnotdosth.结构可知，空格处应填入动词

原形。根据首句可知，脸书正在利用广告宣传手段严厉打击加密数字货币。本句进一

步解释，它不会对经常做具有误导性或欺骗性促销活动的金融产品做广告。结合备选

动词原形可以推断出，display〃展示”符合题意，故为答案。

2（分数：3.55）

填空项1:（正确答案：0）

解析：形容词辨析题。由空格后名词currencies可推知，空格处应填入形容词作

定语。空格后and表示并列关系，initialcoinofferings"首次代币发行”使用的是虚拟

货币，故and之前的短语currencies应与其意思相近。结合备

选项可以推断出，virtual“虚拟的”符合题意，故为答案。

3.（分数：3.55）

填空项1:（正确答案：K）

解析：名词辨析题。分析句子结构可知，空格前为介词of,空格处需填入名词，与

withoutfearof构成短语，作状语。空格后or表示并列关系，deception意思是“欺骗

”,空格处语义应与其相似，应为贬义。结合备选项可以推断出，scams"骗局，诡计”

符合题意，故为答案。

4.（分数：3.55）

填空项1：（正确答案：H）

解析：名词辨析题。分析句子结构可知，空格处所在短语作句子主语，形容词

spectacular修饰主语中心词，所以空格处应填入名词。根据句意可知，各类投资者和

投资公司对bitcoin"比特币”和许多其他的加密数字货币的兴趣激增，由此可以推断出

这种现象的原因是数字货币价格上涨。结合备选项，increase"增力n,增多”符合题意，

故为答案。

5.（分数：3.55）

填空项1:（正确答案：A）

解析：动词辨析题。分析句子结构可知，that引导的定语从句中，第一个谓语动

词为promise,第二个谓语动词用了现在完成时结构，因此空格处应填入动词的过去分

词形式。根据句意可知，比特币等数字货币的过分繁荣已经导致高回报骗局的出现，

这必然会引起美国证券交易委员会的关注和调查。结合备选项可以推断出,attracted"吸

引”符合题意，故为答案。考生需要注意的是，本句中的schemes并不是“计划，规

划”的意思，而是“阴谋，诡计”。

6.（分数：3.55）

填空项1：（正确答案：J）

解析：副词辨析题。空格所在句子中主干成分完整，空格前act为动词，空格处

应填入副词。根据前文可知，虚拟数字货币存在隐患。本句中美国证券交易委员会主

席杰伊•克莱顿在演讲中提出改进要求：市场专业人员做事要，对自己坚持高标准。结

合备选项可以推断出,responsibly"可靠地，可以信赖地”符合题意，故为答案。

7.（分数：3.55）

填空项1：（正确答案：I）

解析：副词辨析题。分析句子结构可知，空格所在的句子是对上一句的承接，空

格前面是逗号，后而是介词短语，空格处可填入副词。根据句意可知，杰伊•克莱顿在

上一句表明市场专业人员做事要有责任心，对他们自己坚持高标准。这里进一步地表

明他的所见所感：在代币方面，他们可以做得更好。结合备选项可以推断出，

particularly特别，尤其”符合题意，故为答案。

8.（分数：3.55）

填空项1:（正确答案：D）

解析：名词辨析题。分析句子结构可知，空格处是举例内容，后面接定语从句对

其进一步解释，or后面的pr。m。ti。ns与其并列，空格处应填入名词。根据句意可知，

脸书提供许多例了来说明它的新政策，这些例了包括建议用户将退休金投资比特币的

广告或“无风险”的加密数字货币的促销活动。结合备

选项可以推断出，copy"稿件”符合题意，故为答案。adcopy即“广告文案”。

9.（分数：3.55）

填空项1:（正确答案：C）

解析：动词辨析题。分析句子结构可知，t。与空格处一起构成不定式结构，作

potential的定语，空格处应填入动词原形。根据句意可知，这里是脸书首席执行官马

克寸L克伯格对加密数字货币的看法，他认为加密数字货币有可能从“集中性的体制”

权力。结合备选项可以推断出，capture〃夺取，夺得”符合题意，故为答案。

10.（分数：3.55）

填空项1:（正确答案：L）

解析：名词辨析题。空格前是形容词性物主代词our,因此空格处应填入名词。根

据句意可知，扎克伯格提到加密数字货币存在难以控制的风险，以后会深入研究它们

的利弊，使之更好地应用于我们的。结合备选项可以推断出，services"服务”符合题

意，故为答案。

SectionB（总题数：10,分数：0.00）

Yourweightaffectshowlongyoulive一butit'sextremelycomplicated

A.Weoftenthinkaboutweightlossintheshortterm,hopingtodrop5

poundsintimeforvacationor10intimeforawedding.Ofcourse,thiskindofyo-yo

dietingisn'tthegreatestforourhealth.Ifyou'regoingtoaskhowmuchyoushould

weigh,youwanttothinklongterm一whatweightwillkeepyouhealthy?

B.Thisquestionhasbeenattheforefrontofresearchers1mindsforawhile,

andforgoodreason.Globalobesityratesarehighandsteadilyincreasing,with1.3

billionadultsconsideredoverweightand600millionintheweightrangecategorizedas

obese.

C.Whileit*struethatmuscleweighsmorethanfat,mostpeoplewhoare

carryingaroundafewextrapoundsaredoingsointheformofadipose（月旨肪的）

tissue.Unlikeboneandmuscle,fatcellscangenerateinflammation（炎症）,allowing

ustohealinfectionsandprotectourbodiesfromfurtherdamage.Buthavingtoomany

fatcellscausesourbodiestoreleaseinflammatoryproteinsallthetime.Manystudies

indicatethiscanincreaseourriskofdevelopingcancer.

D.Carryingaroundextrafatcellsalsoaffectsotherphysiologicalpathways,

manyofwhich一highbloodpressure,hyperglycemia（高血糖证）,andhigh

cholesterol,forexample——canleadtopotentiallyfatalheartproblems.

E.Weallneedsomeamountofbodyfat.Sohowmuchistoomuch?Using

BMI（bodymassindex,thebodymassdividedbythesquareofthebodyheight）and

ratesofoverallmortality,scientistsstudyingthisquestioninitiallycametoasurprising

conclusion:Onapopulationlevel,therelationshipbetweenBMIandmortalityformed

aU-shapedcurve,inwhichthelowestpoint（theonewheremortalitywasatitslowest）

wasactuallyataBMIrangeconsiderednearlyoverweight（about24.5,when25is

overweight）.Bringonallthehealthyfatsandcarbs（含碳水化合物的食物）.

F.Butsomescientists一includingAndrewStokes,achronicdiseaseandglobal

healthresearcheratBostonUniversity-----challengedthoseconclusions.Insteadofa

U-shapedcurve,hisgroup'sfollow-upstudiessawtheriskofmortalityincreasewith

higherBMIs.Thelowestriskcategory,hesays,issomewhereinthelow-normalweight

range,andriskincreasesprettyconsistentlyasBMIgoesup.

G.Theearlierstudiesfailedtoaccountfortwoimportantfactors,according

toStokes."Thenormalweightcategoryusedinmostofthestudiescombineslow-risk,

stableweightpeoplewithhigh-riskindividualswhohavelostweight,"hesays.Ifastudy

subjectspendsmostofhislifeobeseandthenlosesweight,hemightaccumulateyears

ofnegativehealtheffects.Notallofthoserisksdisappearwithweightloss."Muchof

theresearchonobesityjustusesasnapshot(简要描述)ofweightcurrently,"says

Stokes.

H.Stokesequatesthistothewaywestudysmoking.Youcan'tsimplycompare

non-smokerstosmokers.Non-smokersincludethosewhohaveneversmokedaswell

asthosewhomayhavesmokedforseveraldecadesandthenquit.

I.AndsmokingitselfisanothercrucialfactorintheseBMIstudies,Stokessays.

Smokingcanpresentahugebiasinestimatingrisksassociatedwithobesity,because

thehabitaffectsbodyweightthroughmetaboliceffectsandreducedappetite.By

failingtotakesmokingintoaccount,youranalysismayincludepeoplewhohavealow

bodyweightbutsmokeheavily,uppingtheirchanceofanearlydeath.Oncethose

outliersareremoved,Stokesandhiscolleaguesargue,therelationshipbetweenexcess

bodyweightandearlymortalityisclear.

J.Ofcourse,therangefornormalBMIisprettybroad.Forexample,someone

whois5'4"hasanormalBMIiftheyweighanywherefrom108poundsto145pounds.

Ifwewanttoknowwhichsliveroftherangeisactuallybest,Stokessays,researchers

havealotmoreworktodo.

K.Andthenthere'sthequestionofwhetherBMIistherightmetrictouseat

all.BMIisoftencriticizedasapoorindicatorofhealth.Becausemuscleweighsmore

thanfat,aweightliftercouldhaveaBMIintheoverweightrange,andthat*stosay

nothingofalltheothervariationsthehumanformcantake.Eventwofolkswiththe

sameBMIandthesameamountofactualbodyfatmightfacedifferentrisksdueto

theiradipose,ifonecarriesmoreintheirbellyandtheotherstoresmoreintheirhips.

StudiesthatcompareBMItosuperiormethodsliketheDexascan,atypeofX-raythat

candetermineexactlyhowmuchbodyfatyouhaveandwhere,showthatthepotential

misclassificationisnottrivial.ButStokesa