You have made a serious mistake.

你犯了一个严重的错误。

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She made a serious mistake.

她犯了一个严重的错误。

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But early on he made a serious mistake.

但他早年时犯了一个严重的错误。

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"That's when we knew a serious mistake had been made, " Valdivieso told the Times.

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Ask Jon Corzine if leverage is a killer when you make a serious mistake in judgment.

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Last year, in the final days of a Republican-led Congress, lawmakers made what some consider a serious mistake.

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