And at last, one by one, the ropes were all gnawed through.

最后，那些绳子全被咬断了。

They obtain the wood for their dams and huts by gnawing through the branches of trees, and even through the trunks of small ones, with their sharp front teeth.

海狸用自己那尖而长的前牙不断地噬咬大树的细枝，它们甚至还会咬断小树的主干，从而为自己的小屋和水坝储存木材。

Back in the paleolithic days, when food was scarce, you'd have had to gnaw through nearly a metre of chunky, fibrous sugar cane to get the same amount of energy you can now glug down via a single can of Coke.

回到旧石器时代，当食物匮乏的时候，你必须啃断近一米厚的纤维状甘蔗才能获得与现在一罐可乐相同的能量。