Dogswillrefusefoodofferedbypeoplewhohaverefusedtohelpth...
問題詳情：Dogswillrefusefoodofferedbypeoplewhohaverefusedtohelptheirowners,someresearcherssaidlastFriday.Thestudyledbytheresearchersshowedthatdogshavetheabilitytoco-operate(合作)socially-anabilityfoundi...