题目内容：
请根据以下内容回答1-15题TakingaNapDuringtheDay
MedicalexpertssaymostAmericansdonotget1sleep.TheysaymoreAmericansneedtorestforashortperiodinthemiddleoftheday.Theyareadvisingpeopletosleeplightlybefore2withotheractivities.
Onestudyearlierthisyearfoundthatpersonswhosleepforafewminutesduringthedaywereless3todieofheartdisease.Thestudyfollowedmorethan2,300Greekadults4aboutsixyears.Adultswhorestedforhalfanhour5threetimesaweekhada37presentlowerriskofdyingfromheartdiseasethanthosewhodidnotnap.
Studyorganizerssaidthestrongestevidencewasinworkingmen.Theysaidnapsmightimprove6bymitigatingtensioncausedbywork.
SomeEuropeanandLatinAmericanbusinesseshavesupportedthe7ofnappingformanyyears.Theyurgepeopleto8work,gohomeandhaveanapbeforereturning.IntheUnitedStates,somecompaniesletworkersrestbrieflyintheiroffices.Theybelievethisreduces9andaccidents,and10increasestheamountofworkapersoncando.
Sleepexpertssayitislikelythatpeoplemakemoremistakesatworkthanatothertimes.Theysaypeopleshouldnotcarryoutimportantdutieswhentheyfeel11Andtheysaythebestthingtodoistotakeanap.Abouttwentyminutesofrestis12youneed.Expertssaythisprovidesextraenergyandcanincreaseyoureffectiveness13theendoftheday.Butexpertswarnthatanap14lastnomorethantwentytothirtyminutes.Alongernapwillputthebodyintodeepsleepandwakingupwillbe15
A sweet
B sound
C bad
D enough
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