牢狱生活使他变得残暴了。

He was brutalized by the experience of being in prison.

《柯林斯英汉双解大词典》

这个方法大体上听起来很奇怪，不人道而且心怀恶意，但我我可不是让你变得残暴，而是让你不再把你妈妈看成是一个“人”，把她当成一个危险物品就行。

Basically, weird and inhuman and mean as it sounds, and I don't mean for you to be cruel, but stop treating your mother like a human being. Treat her like the hazard she has become.

youdao

要一个怎样的理由方能使人变得如此残暴不仁？

What possible justification could make anyone act so barbarously?

youdao

Because the wardens-- people off the street, randomly divided- were becoming so oppressive.

因为随意找来的，随机分配的典狱长们-,变得非常残暴。

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