资源描述：
《2017届高考英语备考 专题17 阅读理解之说明文》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、限时训练——阅读理解之说明文1.【•湖北卷】Theoddnessoflifeinspaceneverquitegoesaway.Herearesomeexamples.Firstconsidersomethingassimpleassleep.Itspositionpresentsitsownchallenges.Themainquestioniswhetheryouwantyourarmsinsideoroutsidethesleepingbag.Ifyouleaveyourarmsout,theyfloatfreeinzerogra
2、vity,oftengivingasleepingastronautthelookofafunnyballed（芭蕾）dancer.“I’maninsideguy,”MikeHopkinssays,whoreturnedfromasix-monthtourontheInternationalSpaceStation.“Iliketobewrappedup.”Onthestation,theordinarybecomesstrange.TheexercisebikefortheAmericanastronautshasnohandleba
3、rs.Italsohasnoseat.Withnogravity,it’sjustaseasytopedalviolently.Youcanwatchamoviewhileyoupedalbyfloatingamicrocomputeranywhereyouwant.Butstationresidentshavetobecarefulaboutstayinginoneplacetoolong.Withoutgravitytohelpcirculateair,thecarbondioxideyouexhale(呼气)hasatendenc
4、ytoformaninvisible（隐形的）cloudaroundyouhead.Youcanendupwithwhatastronautscallacarbon-dioxideheadache.LeroyChiao,54,anAmericanretiredastronautafterfourflights,describeswhathappensevenbeforeyoufloatoutofyourseat,”Yourinnerearthinksyour’refalling.Meanwhileyoureyesaretellingyo
5、uyou’restandingstraight.Thatcanbeannoying—that’swhysomepeoplefeelsick.”Withinacoupledays—trulyterribledaysforsome—astronauts’brainslearntoignorethepanickysignalsfromtheinnerear,andspacesicknessdisappears.Spacetravelcanbesodelightfulbutatthesametimeinvisiblydangerous.Fori
6、nstance,astronautslosebonemass.That’swhyexerciseisconsideredsovitalthatNationalAeronauticsandSpaceAdministration(NASA)putsitrightontheworkdayschedule.Thefocusonfitnessisasmuchaboutscienceandthefutureasitisaboutkeepinganyindividualastronautsreturnhome,and,moreimportantly,
7、howtomaintainstrengthandfitnessforthetwoandahalfyearsormorethatitwouldtaketomakearound-triptoMars.1.Whatisthemajorchallengetoastronautswhentheysleepinspace?A.DecidingonapropersleeppositionB.ChoosingacomfortablesleepingbagC.SeekingawaytofallasleepquicklyD.Findingarighttim
8、etogotosleep.2.Theastronautswillsufferfromacarbon-dioxideheadachewhen_____.A.theycirclearoundontheirbik
