He used a phrase I hate: "You have to be cruel to be kind."

他用了一句我讨厌的习语：“要想善良，就得残忍。”

《柯林斯英汉双解大词典》

He didn't mean to be cruel but I cried my eyes out.

他并非有意苛刻，但我还是大哭了一场。

《柯林斯英汉双解大词典》

We shouldn't be cruel to animals.

我们不应该对动物残忍。

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Later,Helen learned that nature could be cruel as well as beautiful.

VOA: special.2009.11.15

And this is line 679: Why should you be so cruel to yourself, And to those dainty limbs which nature lent For gentle usage and soft delicacy?

在第679行：，你为什么要对自己那么残忍，对于大自然赋予我们的四肢,只文雅的使用和温和的对待佳肴？

耶鲁公开课 - 弥尔顿课程节选

The message of the flood story also seems to be that when humans destroy the moral basis of society, when they are violent or cruel or unkind, they endanger the very existence of that society.

而洪水所表达的信息是,当人类毁掉了社会的道德根基，当人类变得暴力，残忍，这都会危及到人类社会的存在。

耶鲁公开课 - 旧约导论课程节选

It would also be cruel to run brain scans on someone who was possibly facing the moment of death.

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Speculating on whether Stanford will have a similar happy return to health upon release would be cruel at this point I feel.

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Time can be cruel toward even the most enduring of human creations.

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