1 sentence

1. 峰顶的氧气只是海平面的三分之一。

   fēng​dǐng de yǎng​qì zhǐ​shì hǎi​píng​miàn de sān​fēn​zhī​yī.

   There's only one-third as much oxygen at the summit as there is at sea level.

   Source: UM-Corpus: Subtitles