The most physically demanding stroke, the butterfly features the simultaneous overhead stroke of the arms combined with the dolphin kick.

对身体条件最苛求的泳姿，蝶泳的特色是两臂同时越过头顶结合海豚式打腿。

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Butterfly: a stroke made in the prone position where both arms are lifted simultaneously out of the water and flung forward, in combination with the dolphin kick.

蝶泳：一种泳姿。即采用俯卧姿势，双臂同时在水面之上前挥划水，结合身体做海豚式打水。

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