First, though, valuable nesting places must be defended from property thieves. 不过先得保护好来之不易的筑巢地 免得被其他鸟类占据
When the first polar explorers headed south, 第一批极地探险家前往南方时候
When the first explorers descended, 第一批探险家进入这个洞后
However, human beings are seldom the first to reach these black, damp places. 但是 人类绝非 这个阴暗潮湿地界的第一位到访者
Yet these depths were first explored only two years before man landed on the moon. 然而人类直到登月前两年 才第一次进入这个深渊
At dawn the first adult midges start to break out. 黎明时分 第一只成蚊破蛹而出
For many this is their first journey across the Himalayas. 许多蓑羽鹤都是第一次 踏上穿越喜马拉雅的旅程
These are the first intimate images of snow leopard ever filmed in the wild. 这是在野外环境中 第一次近距离拍摄雪豹
and take their first steps in the outside world. 第一次踏足这个陌生的户外世界
they would never survive their first winter. 它们肯定无法活过第一个冬天