As the sun begins to set, 太阳落下时

46. Towering forests can eventually reach the height
    高耸的巨藻森林最终可以达到
47. of a 12-storey building.
    12层楼的高度
48. These forests are nurseries for young horn sharks.
    这些森林是幼年角鲨生长的温床
49. As the sun begins to set,
    太阳落下时
50. they leave their daytime shelter
    它们离开白天的庇护所
51. and set off into the heart of the kelp forest to find food.
    前往巨藻森林中心寻找食物
52. Barely half a metre long, this little shark is extremely vulnerable.
    这条只有半米长的鲨鱼非常脆弱

来自《行星地球 第三季 第二集 Planet Earth S03E02 海洋》第 49 行