The only flaw in his character seems to be a short temper.

他性格中唯一的缺点似乎就是脾气急躁。

《柯林斯英汉双解大词典》

The only flaw is the slightly slow response times when you press the buttons.

惟一的缺陷就是当你按按钮时稍慢的反应时间。

《柯林斯英汉双解大词典》

Being shy was the only flaw in his character.

害羞是他性格里的惟一缺陷。

youdao

The only flaw in his innings came on 60 when he edged a chance to VVS Laxman at first slip, which was dropped.

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But it is the only flaw I see in the plan.

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His only flaw was a slightly underrotated quadruple salchow.

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