我十几岁的时候腼腆得很。

As a teenager I was painfully shy.

《牛津词典》

我十几岁的时候，正值冷战时期。

Back in my teen years, it was the Cold War.

youdao

你十几岁的时候是什么样子的？

What was it like when you were a teenager?

youdao

the first was it didn't bother with the established baseline of what percentage of teenage girls had received an unwelcome sexual advance in the day to day actions with people.

第一个问题是,它并没有涉及到底量度的基准,到底这些十几岁的女孩子们,在白天与人正常交往的时候,所受到的性挑逗的比例为多少。

麻省理工公开课 - 媒体、教育、市场课程节选

When he was a teenager and he would draw cartoons for them and he even dabbled in children's books

当他十几岁的时候，他为他们画漫画，也涉猎儿童图书，

和男朋友在一起 - SpeakingMax英语口语达人