Pi even shows up in the bends of rivers — their sinuosity, specifically.

π甚至出现在河流弯道——具体说来是河流的曲折度。

The new moon illumined part of the sky and a mist hovered like a veil over the sinuosities of the river.

新月照亮了天空的一部分， 薄雾像面纱一样笼罩在蜿蜒的河流上。