日期:
来源:雅诚德英语网
Because sloth bears are smaller than brown and polar bears and are under greater threat from dangerous animals, they may have adopted the extra precaution of carrying their cubs.
因为树懒的体型比棕熊和北极熊要小,而且面临着更大的来自危险动物的威胁,所以它们可能会带着幼仔采取额外的预防措施。