一旦你形成了良好的发球姿势，那么要做到每一次都将球抛到相同的位置，这一点非常关键。

Once you've developed a sound service motion, it's important that you toss the ball into the same spot each and every time.

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这位24岁的俄罗斯红粉2009年一直处在伤病带来的痛疾之中。虽然她新的发球姿势还不娴熟，但去年秋季还是表现得不错(尽管时不时地还会走点老路)。

The 24-year-old Russian struggled with injuries in 2009 and couldn't master a new service motion, but she played better in the fall (and also reverted to her old service motion).

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在发球准备姿势中本部分的关键是在你再完成屈膝时重心平衡分配在两脚前脚掌之间。

The key to this particular part of the service preparation is to have your weight equally distributed on the balls of each foot by the time you reach maximum knee bend.

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