It has to be proved that they are the guilty party.

尚需证明他们是有过错的一方。

《柯林斯英汉双解大词典》

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We know he is the guilty party, because we saw him take the money.

我们知道他是有罪的一方，因为我们亲眼看到他拿钱的。

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Glenavon's penalty was also for hand-ball, Andrew Kilmartin the guilty party this time from Sammy Stewart's cross.

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Fortunately, with your help, this time around it will be much easier to identify the guilty party.

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Another guilty party in the overspending on unproven talent at the professional level was the Baltimore Orioles.

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