My daughter is nine years old.

我的女儿九岁了。

youdao

I was only nine years old at that time.

我那时候只有九岁。

youdao

I started playing when I was nine years old, and football got me through difficult periods.

我从九岁开始踢球，足球帮助我度过了困难时期。

youdao

He was eighty-nine years old. At his funeral, many family members and friends honored him by wearing red clothes.

VOA: special.2009.03.22

A child eight or nine years old with what used to be called Adult Onset Diabetes.

岁或者9岁的小孩,竟然得了曾称为成年始发性糖尿病的疾病

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

Milton's nearly twenty-nine years old when he writes Lycidas.

写《利西达斯》的时候弥尔顿将近29岁了。

耶鲁公开课 - 弥尔顿课程节选

At twenty-nine years old with thirty looming, I want to be prepared for life.

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Sure, she is only nine years old, but other life choices are already on her horizon.

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When I was nine years old, my father decided to make a major change in his career.

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