My father's name is Niu Jiansheng, he is thirty-eight years old this year.

我的爸爸叫牛建生，他今年三十八岁了。

youdao

The Levites thirty years old or more were counted, and the total number of men was thirty-eight thousand.

利未人从三十岁以外的都被数点，他们男丁的数目共有三万八千。

youdao

Mr Carker was a gentleman thirty-eight or forty years old, of a florid complexion, and with two unbroken rows of glistening teeth, whose regularity and whiteness were quite distressing.

卡克先生是一位三十八岁或四十岁的有身份的先生，脸色红润，有两排完整发亮的牙齿，那种整齐和白色使人看了十分难受。

youdao

He was thirty-eight years old. The Baseball Writers Association of America held a special election.

VOA: special.2010.04.11

One evening, I found myself in such a place with a thirty-eight-year-old elementary-school teacher who had spent more than ten years plying Match.com and Nerve.com, as well as the analogue markets, in search of someone with whom to spend the rest of her life.

NEWYORKER: Looking for Someone