The baby is three months old.

这婴儿三个月大了。

《牛津词典》

Our daughter could walk when she was nine months old.

我们的女儿九个月大就会走路了。

《牛津词典》

He's five months old.

他有五个月大。

youdao

We reported last week that Helen Keller suffered from a strange sickness when she was only nineteen months old.

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This thing this new invention is three months old at this point.

在此刻，这一新的发明却,已经有三个月的历史了。

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His family moved to Texas when he was only three months old.

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By the time of publication, the documents would be more than 14 months old.

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Only 3 months old, the Grammy Museum goes well beyond the famous music awards.

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The son of a US serviceman, Elliott left England when he was six months old.

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