Once upon a time there was a beautiful princess.

从前，有一位美丽的公主。

《牛津词典》

Traditional stories make use of formulaic expressions like 'Once upon a time...'.

传统故事采用“从前…”一类的套语。

《牛津词典》

Once upon a time there was a princess...

从前有一位公主…

《牛津词典》

Once upon a time there was a fearsome ogre whose roar terrorized the magical land of Far Far Away.

VOA: standard.2010.05.27

And once upon a time they actually were thinking about knocking it down

从前，人们也想过要拆毁它，

中央车站的历史 - SpeakingMax英语口语达人

Yes, China is also playing a geostrategic game to win the support of African (and Latin American) states, which it has, for a long time, courted as a check against perceived American and (once upon a time) Soviet hegemony.

FORBES: What's The Long Term Vision For China's Increased Investment In Africa?

Once upon a time, a friendly dragon lived in the heavens above Halong Bay.

BBC: The perfect trip: Vietnam

Although once upon a time I had a staff job with all the appurtenances.

BBC: Class calculator: A US view of the class system