Until they can stand, 在它们能站起来之前

18. A relic from the Ice Age, a baby Saiga antelope,
    一种冰川时代存活至今的生物 高鼻羚羊幼崽
19. just three hours old.
    出生才三小时
20. His only company, his twin.
    陪伴它的只有它的孪生兄弟
21. Until they can stand,
    在它们能站起来之前
22. their mother has left them hidden in the grass.
    母亲会将它们藏在草丛中
23. They should be safe, as long as they remain quiet.
    这样应该很安全 只要保持安静
24. For these calves, the clock is already ticking.
    对这两只小羊来说 时间紧迫

来自《行星地球 第二季 第五集 Planet Earth S02E05 草原》第 21 行