Before the party, your friends and family make a big paper ball.

在生日宴会前，你的朋友们和家里人做一个大纸球。

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Using Your Hands to Fidget with Small Objects – a pen, paper ball, etc.

用手摆弄东西 ——笔，纸团等。

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He screwed the paper into a ball and tossed it into the fire.

他把那片纸揉成一团扔进了火里。

《柯林斯英汉双解大词典》

Distressed and defaulted paper, however, continued to knock the cover off the ball as credit opportunity investors sought out wide-margin opportunity.

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But a good ball coach will tell you that no game is won on paper, but on the field.

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Using those simple measurements and the equations presented in the paper, the researchers were able to predict which half of the roulette wheel the ball would end up in about 59% of the time.

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