'he continued:' the outer bow (2), the one we also see sometimes, comes when sunlight reflects twice in each raindrop.

最外层的那道彩虹(图示2)是在太阳光在每滴雨滴内反射两次形成的。

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Rainbows sometimes appear as two concentric bows with the inner one called the primary bow and the outer one the secondary bow.

彩虹有时会以两条同心圆弧形态出现。内弧称为主虹，外弧称为副虹或霓。

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