你在学习发反手上旋球和下旋球。

You are learning the backhand topspin and backspin serves.

youdao

我擅长反手上旋球。

I am good at the backhand topspin.

youdao

发球方法包括，反手上旋球和下旋球，正手上旋球和下旋球。和高抛发球。

Services include the backhand topspin and backspin serves, the forehand topspin and backspin serves, and the high toss service.

youdao

You do that eight billion times in your life and you can hit a good top spin backhand.

如果你把这个动作做上八十亿次,那你一定能打个漂亮的反手上旋球

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