她给了我一块饼干——她从纽约最好的面包店买的维也纳式新月形饼干——开始了一生中第一次严肃的谈话。

She brought me a cookie – a Viennese crescent she got from the best bakery in New York – and initiated the first of a life time of serious talks.

youdao

像这样的机会一生也许只会遇到一次。

An opportunity like this comes once in a lifetime.

《牛津词典》

如果你正在寻找一次一生难忘的冒险经历，那么来一场蹦极，从直升机上跳到活火山口怎么样？

If you're looking for the adventure of a lifetime, how about going bungee jumping off a helicopter into the crater of a live volcano?

youdao

And then other people are really excited because it's a once-in-a-lifetime opportunity

而另外一些人真的很兴奋，因为这是一个一生只有一次的机会，

正准备奥运会 - SpeakingMax英语口语达人