Helicopters require a tail rotor to counteract the rotor torque; this and the articulated head complicate flying, construction and maintenance enormously.

需要直升机尾桨抵消转子力矩；这和阐述头复杂飞行，建造和维修极大。

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The head, front legs, hind legs, and tail of the Japanese flying squirrel are connected by a membrane of skin, which allows the squirrel to glide from tree to tree.

日本鼯鼠的头部、前肢、后肢还有尾巴都有皮膜相连，这使得它可以在树与树之间滑翔。

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