The football unit is coming in the spring, and they split the teams up into shirts and skins.
开春就要上橄榄球课了，到时候球员就会被分成“布衣”和“皮衣”两队。
格列佛游记（原版）
His clothes, shirt, and skin, were all of the same colour.
他的衣服、衬衫和皮肤，都是同一种颜色。
英语百科
Shirts versus skins
（重定向自Shirts and Skins）
Shirts versus skins (or shirts and skins) is a common form of denoting team affiliations in a pick-up game (an informal sports game); typically when played by males on a public court or field, such as in a city park or schoolyard. The practice involves the members of one team wearing shirts while the ones of the other team don't. This is used in the absence of uniforms.