I apologize if I had offended you, but I assure you it was unintentional.

如果我冒犯了你，我向你道歉，但我向你保证我不是故意的。

youdao

I am very sorry if I had done anything wrong to you, but I am sure that it was unintentional.

如果我当时对你作错了什么事，我向你表示抱歉。但我敢保证我不是故意的。

youdao

Perhaps he had slightly misled them, but it was quite unintentional.

或许他有一点误导他们了，但完全是无意的。

《柯林斯英汉双解大词典》

Verlander said it was unintentional.

WSJ: Niese outpitches Verlander in Mets' win

Bikram Singh accused Pakistan of planning the attacks that left the two Indian soldiers dead making clear he felt it was not an unintentional skirmish and warned of possible retaliation.

NPR: Pakistani Soldier Dies In Latest Attack In Kashmir

Yet technology could worsen the problem it was meant to solve, as touchscreen voting systems may contain bugs, intentional or unintentional, buried deep within their software, that will be virtually impossible to trace.

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