He spent hours throwing a tennis ball against a wall.

他花了数小时对着一堵墙扔网球。

《柯林斯英汉双解大词典》

My father would burst into the kitchen bouncing a tennis ball.

我父亲会拍打着网球闯进厨房。

《柯林斯英汉双解大词典》

I spent many hours mindlessly banging a tennis ball against the wall.

我花了好多个小时单调地对着墙打网球。

《柯林斯英汉双解大词典》

For example, a portion of pasta according to the U.S. Department of Agriculture would be about the amount of pasta that would be the size of a tennis ball.

比如说,意大利面的每日摄入量,根据美国农业部,是如此的份量,大概和网球一样大小

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Now if you lived in a culture where the only meat that got served was the size of a deck of cards, and the only pasta that got served was the size of a tennis ball, there wouldn't be such problems, but that's not the case.

如果我们生活在一个,肉类每日摄入量是一副牌大小,或者意大利面只有网球大小的环境中,问题就不会存在,可惜这不是现实

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Suppose that we have a tennis ball moving across the screen for 1 second.

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There, on the right side of his brain, was a tumor the size of a tennis ball.

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This number is calculated by considering both horizontal speed and vertical bounce of a tennis ball off a court.

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