I once went out with a French man.

我曾与一个法国人恋爱过。

《柯林斯英汉双解大词典》

I once met your mother.

我曾经见过你母亲。

《牛津词典》

I once went camping at Lake Michigan with a friend.

我曾和一个朋友去密执安湖野营。

《柯林斯英汉双解大词典》

Let me tell you about a person I once knew who liked to play card games for money.

VOA: special.2009.10.11

I once went to visit the summer palace that he created and that Nicholas II loved so much there.

我曾到过他修建的夏宫看过,据说尼古拉二世特别喜欢那个地方

耶鲁公开课 - 欧洲文明课程节选

I once picked up a guy on Broadway and he was drunk,

我还在百老汇载过一个人，当时他喝得很醉，

记忆犹新的乘客 - SpeakingMax英语口语达人

Or am I over-thinking this and, instead, I once again acted like a clod?

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Mr. MacLean didn't have the unforgettable luck I once did while working at NBC years ago.

WSJ: Open-Air Status Symbols

As a contrary example, I once inadvertently started a false rumor that company-wide layoffs were looming.

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