they might have reached if their reign had continued. 能达到何种新的高度 谁都不知道

332. For 150 million years,
     1.5亿年间
333. dinosaurs ruled the planet.
     恐龙统治着地球
334. Who knows what new heights
     如果它们继续统治下去
335. they might have reached if their reign had continued.
     能达到何种新的高度 谁都不知道
336. But in the story of life...
     但在生命的故事中
337. ...nothing lasts forever.
     一切都不是永恒的
338. [The End]
     [本集结束]

来自《我们星球上的生命 第一季 第五集 Life on Our Planet S01E05 巨兽阴影下》第 335 行