You could also do single arm drill with your arm down by your side. This is the way we like to do.

你还可以进行单臂划水训练，一只手臂置于体侧。

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During, or at the end of the arm pull-down of the first stroke after the start and after each turn, a single downward butterfly kick is allowed, but not required, followed by a breaststroke kick.

出发后或每一次转身之后，在第一次大划手之当时或之后，一次向下蝶式踢腿是被允许的(非必要的)然后拌随一次蛙式踢腿。

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