C
Here’sanewwarningfromhealthexperts：sittingisdeadly.Scientistsareincreasinglywarningthatsittingforlongperiods，evenifyouexerciseregularly，couldbebadforyourhealth.Anditdoesn’tmatterwherethesittingtakesplace—intheoffice，atschool，inthecarorbeforeacomputerorTV.Justtheoverallnumberofhoursittakescounts.Severalstudiessuggestpeoplewhospendmostoftheirdayssittingaremorelikelytobefat，haveaheartattackorevendie.
Whilehealthofficialshaveissued(发布) guidelinesadvisingontheleastamountsofphysicalactivities，theyhaven’tsuggestedpeopletrytolimithowmuchtimetheyspendinaseatedposition.
“Afterfourhoursofsitting，thebodystartstosendharmfulsignals，”saidEkblomBakoftheSwedishSchoolofSportandHealthSciences.Sheexplainedthatgenescontrollingtheamountofglucose(葡萄糖) andfatinthebodystarttoshutdown.
Evenforpeoplewhoexercise，spendinglongperiodsoftimesittingatadeskisstillharmful.TimArmstrong，aphysicalactivityexpertattheWorldHealthOrganization，saidpeoplewhoexerciseeverydaybutstillspendalotoftimesittingmightgetmorebenefitsifthatexercisewerespreadacrosstheday，ratherthaninasinglehour.
Stillinastudythattrackedmorethan17,000Canadiansforaboutadozenyears，researchersfoundpeoplewhosatmorehadahigherdeathrisk，whethertheyexercisedornot.
Expertssaidmoreresearchisneededtofigureoutjusthowmuchsittingisdangerous，andwhatmightbepossibletooffsetthoseeffects.
“Peopleshouldkeepexercisingbecausethathasalotofbenefits，”EkblomBaksaid.“Andwhenthey’reintheoffice，theyshouldtrytointerruptsittingasoftenaspossible.”
28．Sittingtoomuchisdangerousbecauseitcan.
A．makeapersonunabletoexerciseenoughinaday
B．destroythebalanceofglucoseandfatinthebody
C．increaseglucoseandfatinthebody
D．makeapersonbecomelazy
答案 B
解析 细节理解题。根据第三段最后一句“She explained that genes controlling the amount of glucose(葡萄糖) and fat in the body start to shut down.”可知B正确。
29．Theunderlinedword“offset”inParagraph6mostprobablymeans“”．
A．turnto B．workout
C．getridof D．makeuseof
答案 C
解析 词义猜测题。根据划线词所在句句意为：专家们说，还需要做些研究来确定到底坐多久是危险的，以及能够去除这些不良影响的方法。由此可知，划线部分应该是“去除，除掉”之意。
30．IntheopinionofEkblomBak，whenatwork，you’dbetterhavearestby.
A．sendingyourfriendsemails
B．takingawalkaroundyouroffice
C．chattingonlineorplayingcomputergames
D．listeningtomusicwhilesitting
答案 B
解析 细节理解题。根据文章最后一段可知，在办公室时应该尽可能经常的打断久坐这种状态，因此选B。
31．Whichofthefollowingmightbethebesttitleforthepassage?
A．SideEffectsofSittingTooMuch
B．Don’tSitTooMuchWhileWorking
C．MoreandMorePeopleSitTooMuch
D．SittingTooMuchCouldBeDangerous
答案 D
解析 标题归纳题。文章主要介绍久坐对健康的危害，所以选D。
