One day a larger ship anchored offshore.

一天，一艘更大的船在近海抛锚。

《柯林斯英汉双解大词典》

She gives herself one day a week off, on Thursdays.

她每周放自己一天假，在星期四。

《柯林斯英汉双解大词典》

But one day a pig got hungry.

但是有一天，一只猪饿了。

youdao

Poor Billy! A bullet came out of the sky one day and tore a great hole in Billy's chest.

VOA: special.2009.12.12

for why you became afraid of dogs is that one day a dog came up and he was a neutral stimulus.

你之所以害怕狗,是因为，某天有只狗向你跑来,狗是一个中性刺激。

耶鲁公开课 - 心理学导论课程节选

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

This may be one day a week or one day a fortnight they may exclude.

BBC: Couple drinking

Because I'm allowed one day a month where I'm just in a horrible, horrible mood.

NPR: Soft Housing Market Catches Some Between Homes

One day a woman pulls up in front of the store driving a milk truck.

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