Ravi says the air is still unbreathable.

拉气仍然无法呼吸。

The air up there is unbreathable.

上面气令人无法呼吸。

Some were probably put off by practical challenges, such as clogged roads, unbreathable air and patchy telecoms networks.

有些人可能因实际挑战而迟，例如道路堵塞、气难以呼吸和电信网络不稳定。

One by one, the astronauts emerge  from their Starships and walk with light, bounding steps across the planet's surface, protected  by spacesuits from the extreme temperatures and unbreathable atmosphere.

宇航员一一从他际飞船中走出来， 在太服保护下，轻快地行走在地球表面，免受极端温度和难以呼吸大气影响。