Canyouwalkinastraightline?Thequestionismuchmoredifficulttoanswerthanyouthink.Believeitornotyoureyesandearshelpyoutowalk!

ArecentexperimentheldinJapanshowsthatitisalmostimpossibleforpeopletowalkexactlystraightfor60meters.

TheTokyoUniversityofAgricultureandTechnologyasked20healthymentowalkasstraightaspossiblefor60metersatnormalspeed.

Eachmanhadtowearsockssoakedwithredinkandwalkonwhitepaperfixedflattothefloor.Thefootprintsshowedthatallwalkedinawindingratherthanastraightline.

Researchersfoundthatpeoplereadjusttheirdirectionofwalkingregularly.Theamountofmeandering（曲折前行）differedfromsubjecttosubject.

Thissuggeststhatnoneofuscanwalkinastrictlystraightline.Ratherwemeandermainlyduetoaslightstructuralorfunctionalimbalanceofourlegs.Sostepsbytheleftandrightlegsofapersonaredifferent.

Asaresultalthoughwemaystartwalkinginastraightlineseveralstepsafterwardswehavechangeddirection.Eyesighthelpsustocorrectthedirectionofwalkingandleadsustothetarget.

Yourearsalsohelpyouwalk.Afterturningaroundalotwithyoureyesclosedyoucanhardlystandstillorwalkstraight.It'sallbecauseyourearsarestillspinningandcan'thelpyoukeepyourbalance.Insideyourinnerearisastructurecontainingliquids.Insideyourearsaremanyminutehair-likestructuresthatmovearoundastheliquidflows.

Whenyouspintheliquidinsidealsospins.Thedifferenceisthatwhenyoustoptheliquidcontinuestospinforawhile.Dizziness（眩晕）istheresult.

Forthemomentalthoughyoureyesighttellsyoutowalkinastraightlineyourbrainlistenstoyourspinningearsthusyoudon'twalkinastraightline!

1．Whenyouwalkfor60metersyou .

A．canwalkstraightwithouteffort

B．meanderatfirstandinwhilewalkinastraightline

C．can’twalkexactlystraightatanytime

D．canalmostnotcoverthedistanceinastraightline

2．Whymosttimecanweonlywindourway?

A．Becauseoureyesdirectusto.

B．Becauseourearsdirectusto.

C．Becauseofaslightstructuralorfunctionalimbalanceofour