Maybe letting them go to zero if they had to be positive or maybe by making them go to infinity.

当它为正数时，让它趋于零，或者趋于无穷大。

youdao

The first column read "Win-Win. " To have a check mark in this column, the comment (made by either boy) had to be positive-a nice thing to say and to hear. The next column was headed "Win-Lose.

第一列为“双赢”，本专栏里面有一个核选标记，就是说出的和听见的评论（来自另一个男孩）必须是积极的。

youdao

Khoza said a huge number of international visitors would be in South Africa in 2010 and each one of them had to leave with a positive image of the country.

科扎说大量的国际游客2010年将会在南非，我们要给他们每个人都留下积极的印象。

youdao

It was Bridge's good fortune that Carnegie had selected him to be the bearer of this missive, proof positive that he had managed his way back into Carnegie's good graces.

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The biggest hurdle was that the plastic had to be strong enough to hold the positive pressure of air pumped in, says Michael Metta, Sealed Air's technology chief.

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They were eight times more likely to be hepatitis C positive, and eight times more likely to inject drugs than women who had sex exclusively with men.

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