They also didn't last very long due to how quickly they burned through all their stellar fuel — each one existed for just a few million years, it's thought.

由于星球燃料消耗得非常快，所以它们持续的时间也不太长——据说每颗恒星只存在了几百万年。

They also didn't last very long due to how quickly they burned through all their stellar fuel–each one existed for just a few million years, it's thought.

它们也没有持续很长时间，因为它们燃烧所有恒星燃料的速度有多快——据认为，每一个都只存在了几百万年。