怎么形成的？

【 在 vieux 的大作中提到: 】
: Merry Lake in the Moscow region.
: 180 km from Moscow, near the village of Lemeshki, there is this unusual lake in the shape of a smiley face. On the map it is indicated as Black Lake. Its banks are very swampy, and it is unlikely that you will be able to get close.
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FROM 111.30.223.*