but it's discovered that repeated hammering will tire the clam... 但它发现反复敲打会令蛤蜊疲惫
and, as he begins to tire, she supports him close to the surface so that he can breathe more easily. 疲劳的幼鲸被妈妈托上浮上水面好让它呼吸空气
if they tire of tree bark and other survival food 如果它们厌倦了树皮和其它残存的食物