题目内容：
Humanfriendsmaycomeandgo,butahorsecouldbeoneofyourmostloyal,long-termfriendsifyoutreatitright.Horsesunderstandwordsbetterthanexpected,sincehorsescanhearthehumanvoicebetterthanevendogscan,duetotheirparticularrangeofhearing.Andscientistspredictthattrainerscouldhavegreatersuccessiftheyusemoreverbalcommandsintheirhorsetrainingprograms.
Horsespossessexcellentmemories,whichallowhorsestonotonlyrecalltheirhumanfriendsafteralongperiodofseparationbutalsotoremembersomecomplexhumaninstructionsfortenyearsormore.Thebondswithhumansarelikelyanextensionofhorsebehaviorinthewild,sincehorsesvaluetheirownhorserelativesandfriends,andarealsoopentonew,non-threateningacquaintances.Horsesmaintainlong-termbondswithseveralmembersoftheirfamilygroup,buttheyalsointeracttemporarilywithmembersofothergroupswhenformingherds.
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