He knew that Karl could be an implacable foe.

他明白卡尔可能会成为他的死敌。

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He was a celebrity, sometimes a self-parody, a hearty friend, an implacable foe, a man of large faith and large flaws, a melancholy character who persevered, drank deeply and sang loudly.

他是个名人，有时会夸张地自嘲；他也是一个真挚热情的朋友，一个不可阻挡的对手，一个信得坚决，错得执拗的男人；他性格忧郁，坚忍不拔，大口喝酒，放声歌唱。

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Certainly energy companies now face a potentially implacable foe and a re-energized, increasingly hostile bureaucratic apparat.

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You cannot fight a half-war against an implacable foe.

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