Around 80 percent come in underweight and need fattening up.

大约80%的企鹅体重过轻，需要增肥。

You know why they're fattening you up, don't you?

“你知道他们为什么让你长胖吗？”

If you're here much longer, I'm gonna have to buy bigger clothes. Nonsense. You need a little fattening up.

如果你再住久点，我得去买大一号的衣服了。说什么呢。你需要长点肉。

After 15 years away, fattening themselves up in colder climes, they are now back and big enough to compete for a mate.

在远方更寒冷的气候中养精蓄锐了15年后，如今他们回到了这里，壮大到足以为争取配偶而战斗。