One day I will return your help.

总有一天我会回报你的帮助。

youdao

One day I went to see her.

有一天我去看她。

youdao

Perhaps one day I may go on a relaxing holiday.

也许有一天我会去度过一个轻松的假期。

youdao

But I promised myself that one day I would punish Fortunato for his insults to me.

VOA: special.2009.02.07

I tow them to my garage. I like my job. One day I am stuck.

我把他们拖回我的车库，我喜欢这个工作，但是有一天我坏掉了。

耶鲁公开课 - 文学理论导论课程节选

and then one day I'll be like, "Oh, I want to dress like a clown today, so I will."

而可能有时候，我想，“喔，今天我想打扮成一个小丑，然后我就这么做了。”

时尚让人兴奋 - SpeakingMax英语口语达人

God willing one day I will learn how my father died and bring him home.

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One day I asked this retired steel worker for the secret to his success.

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Since leaving the city I have wanted to return, and one day I will.

BBC: This is Seoul week