A friend once in lifetime, I want to cherish.

人生难得一知己，我会用心去珍惜。

youdao

Youth is the most beautiful period in life which comes only once in lifetime.

青春是人一生中最美好的阶段，并且青春只有一次。

youdao

All jazz lovers should come to the Montreal International Jazz Festival at least once in a lifetime.

所有的爵士爱好者一生中都应该至少来一次蒙特利尔国际爵士音乐节。

youdao

As he once told the Houston Chronicle, "A Weed Eater comes along once in a lifetime."

VOA: special.2011.07.19

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

Definitely a once in a lifetime opportunity I'm doing here." These boys say they share the special link of being Scouts no matter where they come from.

VOA: special.2010.08.06

This is a once in lifetime opportunity to save lives and save the country money.

BBC: David Cameron vows to end cheap alcohol sales

Debuting at the same time as "super storm" Hurricane Sandy, the Livestream android app offers a new way for users to share their experience of a once in a lifetime event in real time with their social networks.

ENGADGET: Livestream for Producers Android app update brings live video broadcasts over wireless data connections

This challenge has presented us with a once in a lifetime opportunity to help reshape education in America by recruiting and training the next generation of great American teachers.

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