The golden rule in tennis is to keep your eye on the ball.

打好网球的重要原则是眼要紧盯着球。

《牛津词典》

Remember, keep your eye on the ball.

记住，眼睛盯住球。

youdao

Raj:Maybe you should keep your eye on the ball, Papa.

说不定你应该盯着球看，爸爸。

youdao

In this case, it's best not to keep your eye on the ball.

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Instead, if you whiff, it will serve as the impetus to spend extra time in the batting cage, practice your swing, and attend to the need to keep your eye on the ball.

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Better to keep your eye on the customer ball.

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