At the age of fifteen, he began to learn music, and he did well in it.

十五岁时，他开始学习音乐，而且学得很好。

youdao

When boys get to the age of fifteen or sixteen they eat their heads off.

男孩子到了十五六岁的年龄，食量大得吓人。

youdao

In the summer of 1997, at the age of fifteen, I learned a valuable life lesson.

1997年的夏天，在我15岁的时候，我学到了人生的重要一课。

youdao

At the age of fifteen, he left school and went to work in the music business.

VOA: special.2009.02.08

At this original performance of the mask, the Lady's speech read by the Lady Alice Egerton, age fifteen, ended at line 779 in your text.

面具》最初的表演中，这位女士的演讲由15岁的爱丽丝，埃杰顿女士朗读，在你们书上的第779行结束。

耶鲁公开课 - 弥尔顿课程节选

By the age of fifteen, she was the head of her youth orchestra.

VOA: special.2010.04.09

Sesame Street is aimed at educating and entertaining 65 million Pakistani children under the age of fifteen.

FORBES: Killing 'Sesame Street' In Pakistan

He had gone Clear by the age of fifteen, and the next year he dropped out of high school to join the Sea Org.

NEWYORKER: The Apostate

This feature consists of fifteen lists of people under the age of thirty, each of whom are changing the face of a different business.

FORBES: 30 Under 30: The Brightest Young Stars In Video Games