Young children are beginning their formal education sometimes as early as four years old.

幼儿有时早在四岁时就开始接受正规教育。

《牛津词典》

Jack is only four years old.

杰克只有四岁。

youdao

At that time, my little brother was about four years old and he missed mum all the time.

那时，我的小弟弟大约四岁，他一直想念妈妈。

youdao

When she was about four years old, she heard her mother struggling to play a piece of music on the piano.

VOA: special.2010.04.09

I'm sixty-four years old and I haven't had one second of genius in my entire life.

我已经六十四岁了,这辈子都没有哪怕一秒钟灵光乍现的时候

耶鲁公开课 - 聆听音乐课程节选

Oh, that goes actually way back time when we were like little kids like, four years old,

哦，那其实要追溯到我们是小孩子的时候了，四岁的时候，

和朋友一起逛洛杉矶 - SpeakingMax英语口语达人

One was two years old, one was one years old, one four years old.

NPR: Iraq Finishes Own Investigation of Deaths in Haditha

He was just four years old when his family fled India for the new state of Pakistan.

NPR: Musharraf Denies Pakistan Is Harboring Taliban

And despite being only four years old, the company has customers like Clorox, Target, Facebook and J.

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