I stayed up till four am for the last minute study for the English exam, and when I finally did lie down, I couldn't sleep a wink.

我为了英语考试开夜车，一直开到早上四点，抓紧最后一分钟来学习。等到我最后躺下睡觉，我一点都睡不着。

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He and Stephanie had left Copenhagen around four AM and flown to Paris, where they caught the first Air France shuttle of the day south for Toulouse.

他和丝苔妮在上午四点左右离开哥本哈根到巴黎，在那里他们赶上了当天第一班法国航空南飞图卢兹。

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I am the youngest of four sisters.

我是四姐妹当中最小的。

《牛津词典》

"I am announcing a new international effort to secure all vulnerable nuclear material around the world within four years."

VOA: standard.2010.04.06

and then there's one eating club that's famous for being open until, like, four am,

有一家饮食俱乐部以营业到凌晨四点而出名。

有趣的吃东西协会 - SpeakingMax英语口语达人

And you get the idea. What am I going to do next? I'm going to compare three against four.

我接下来将要怎么做了？,我要拿3和4进行对比，3是小的一个。

麻省理工公开课 - 计算机科学及编程导论课程节选

Lionel Victor says he left his home in Cite Soleil at four AM to walk the two miles to his designated polling station in Delma.

NPR: Haitians Flock to Vote in National Elections

"I am delighted to have committed myself to Celtic for the next four years and I am really looking forward to working with all the other players to try and achieve more success for the club, " said McGeady.

BBC: McGeady has made four appearances for Celtic

My long-suffering partner, Brian Davis, has been hit by a ball during a pro-am on four separate occasions.

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