The theory is that a white sclera surrounding a darker iris and pupil helps people work out where everyone else is looking.

该理论认为，围绕在深色虹膜和瞳孔周围的白色巩膜帮助人们判断出其他人在看哪里。

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Well, it's what we know today as the iris and pupil, round like an apple, at the center of the eye.

就是我们今天所说的瞳孔和虹膜，其形状像圆圆的苹果，在眼睛的中心。

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LASIK eye surgery changes the shape of your cornea—the transparent membrane that arcs over your pupil and the colored part of your eye (iris).

LASIK 眼科手术改变了你的角膜的形状——角膜是覆盖在你的瞳孔和你的眼睛的有色部分（虹膜）上的弧形透明膜。

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