To turn or rotate(a limb) so that the inner surface faces down or back. Used of a vertebrate animal.

使（手，前肢等）掌面向下转或 旋（四肢） 使 其内侧表面朝下或朝后。

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The first and second housings are connected by a hinge device at one end of the first housing, and they rotate so that the front and back faces may be reversed.

第一壳体和第二壳体通过在第一壳体的一端的铰链装置连接，并且所述 壳体可旋转使得前面和后面反转。

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