They found it was a simple matter of Numbers: by wearing many hats, or antigen receptors, regulatory t cells can keep their eyes on a lot of different non-regulatory cells.

他们发现通过戴帽子也就是说其携带的抗原受体，这就成了很简单的数字问题，因为调控T细胞可以盯住很多不同的非调控细胞。

youdao

But they don't keep it simple: I've also seen their nickname listed as The Falcons (al-Sogour) and The Green ( al-Akhdar).

NPR: What's In a Nickname? The Answer Is in the Cup

But for people who don't know about styling or putting clothes together or don't necessarily have a fashion sense, just keep it simple, a pair of jeans, a shirt, a blazer and shoes.

NPR: Styling The NBA

We didn't try to be too cute, we tried to keep it simple and got a big win.

WSJ: Maple Leafs Wilt At Home