每局比赛的第一分球站在中间标志的右边发球，第二次换到左边，第三次又回到右边，如此交替进行。

For the first point of each game, the server stands to the right of the center mark to serve, for the second, to the left, for the third back to the right, and so on alternately.

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每局比赛的第一分球站在中间标志的右边发球，第二次换到左边，第三次又回到右边，如此交替进行。

For the first point of each game, he stands to the right of the center mark to serve. For the second, to the left, for the third back to the right, and so on alternately.

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而发球落点的变化性是高水平双打选手发球技术的重要标志。

The service ball landing point is the key skill in serving the ball in doubles.

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