For the most part, it is the speed at which trolls regenerate that makes them formidable foes.

很大程度上，巨魔再生的速度使他们成为可怕的敌人。

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To choose such formidable new foes in the middle of your life takes bags of self-belief, but it is also pragmatic—and a little poignant.

在中年时期选择如此强大的敌人犹如背负上自信的包袱，但这也有些现实，也点严厉。

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But any team that includes Williams will be the team to beat, despite the potential for some formidable foes.

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Americans found the outcome of the Korean War deeply frustrating, coming so soon after our sweeping victories against formidable foes in WWII.

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Then, there is Mr. Gates' fixation on fighting insurgencies like today's instead of preparing for tomorrow's possible conflicts with more formidable foes like China.

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