NorthAmericanbackbearsareshyanimals.Theyarefearfulbynat...
问题详情：NorthAmericanbackbearsareshyanimals.Theyarefearfulbynature,andwillusuallyrunawayiftheyseeorhearpeople.Becauseofthis,itcanbedifficultforscientiststolearnabouttheseanimals.Inordertostudyblackbea...