He left home at the tender age of 15.

他15岁离家，还少不更事。

《牛津词典》

He took up the game at the tender age of seven.

他在7岁的小小年纪就开始从事这项运动。

《柯林斯英汉双解大词典》

Of course, I had heard that genius could show itself at an early age, so I was only slightly taken aback that I had achieved perfection at the tender age of 14.

当然，我早就听说天才可以在很小的时候就显露出来，所以我只是对自己在14岁的时候就达到了完美有点吃惊。

youdao

Meanwhile, Nina Devani is already the chief executive officer of a technology company at the tender age of 14.

BBC: Will the next Zuckerberg be female?

In January 2004, Mr Saakashvili was elected president of his country with 96% of the vote, at the tender age of 37.

BBC: Profile: President Mikheil Saakashvili of Georgia

David Weir, looking to complete a whole season of playing every minute of every game for Rangers this season at the tender age of 39, should have done better than head a few yards wide after rising above the opposing defence to meet a corner.

BBC: Rangers 3-3 Motherwell