If you are like 90 percent of the world, you are an innie.

如果你和世界上90%的人一样，那你就是凹脐人。

Belly button fluff is especially common in innie belly buttons.

肚脐绒毛在凹脐中尤其常见。

Are you an 'innie' or an 'outie? '

你是‘凹脐人’还是‘凸脐人’？

However, many people like the look of an innie belly button the most.

然而，很多人最喜欢凹脐的样子。

But rivers don't have umbilical cords, so why do they have innies and outies?

但是河流又没有脐带，那它们为什么会有凹凸的区别呢？

But in general, belly buttons have two basic different shapes: 'innies' and 'outies.'

但一般来说，肚脐有两种基本不同的形状：凹脐和凸脐。

And innies are ripe for colonization, not only by lint, hair, and dead skin cells, but also by bacteria.

小狗身上很容易滋生细菌，不仅是棉绒、毛发和死皮细胞，还有细菌。

People used to believe that a doctor could cut the umbilical cord of a baby to shape it into an innie or an outie.

人们曾经相信，医生切断婴儿脐带的手法，可以决定是凹脐还是凸脐。

Rivers also have innies and outies, not belly buttons, but mouths: where rivers flow into the sea, the land either pokes out or bends inward.

河流同样也有凹凸之分，不过不是肚脐，而是河口：在河流入海的地方陆地会向外延伸，或者向内弯曲。

It forms when a doctor snips your umbilical cord, and, depending on how it heals, you could have an outie or, more likely, an innie.

它是由医生剪断你的脐带时形成的，根据脐带的愈合情况， 你可能会出现外脐，或者更可能是内脐。