Losing one might mean never getting the chance to breed ever. 失败一次或许意味着将永远失去生育权
Surprisingly, snow here never melts. 奇怪的是 这里的雪永远都不会融化
troglodytes, animals that never emerge from the caves or see daylight. 穴居动物——从不出洞并且 永远不见天日的动物
but they could never have known that these flooded passageways were actually the beginning of subterranean rivers, 但他们从不知道这些水下通道 其实是地下河的入口
once they have a hold, they never let go. 一旦被它逮住 猎物再无逃脱的机会
they would never survive their first winter. 它们肯定无法活过第一个冬天
African leopards could never survive here, 非洲豹根本不能在这里生存
and show you the planet and its wildlife as you have never seen them before. 展示这个星球的风貌 和你以前从未见过的野生动物