As rivers leave the mountains behind, 河流离开山区之后

78. The Grand Canyon.
    这就是大峡谷
79. This river has cut the world's longest canyon system -
    这条河冲蚀出了世界上最长的峡谷系
80. a 1,000 mile scar clearly visible from space.
    在太空中也能清楚地看到 这条长达1000英里的沟壑
81. As rivers leave the mountains behind,
    河流离开山区之后
82. they gradually warm and begin to support more life.
    河水渐渐变暖 养育的动物也多了起来
83. Indian rivers are home to the world's most social otter -
    印度河里住着世界上最具社会性的水獭
84. smooth-coated otters form family groups up to 17 strong.
    印度水獭的一个家族可多达17名成员

来自《行星地球 第一季 第三集 Planet Earth S01E03 淡水》第 81 行