Some large modern carnivores, such as lions and hyenas, do hunt in organized groups, but T. rex individuals likely acted on their own.

一些现代的食肉动物，例如狮子和鬣狗，均是集体捕猎，但是霸王龙却喜欢独来独往。

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Some of those questioned by prosecutors have said the suspects acted on their own initiative.

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But a top Taliban leader who had been negotiating with Dostum for the surrender of Konduz said the rebellious prisoners were mostly non-Afghan fighters who acted on their own.

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The fact that so few have acted on their own is perhaps an indication of how permissive accounting rules can cause a race to the bottom that, in the end, can lead to scandal or an atmosphere that permits scandal.

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