This story about thirty years ago.

这个故事发生在大约三十年前。

youdao

Dr Martin Luther King's murder took place about thirty years ago.

马丁·路德·金博士遇害于大约三十年前。

youdao

In towns, there were very few bus shelters until about thirty years ago.

三十多年前的城镇里没有太多的汽车候车亭。

youdao

So,just being able to pick one of those up will help our visitors understand how difficult portability was about thirty years ago."

VOA: special.2011.02.15

About thirty years ago, Motorola hooked up with Nextel to bring national two-way push-to-talk service to businesses and government through a public infrastructure network.

FORBES: Connect

Debates have been raging about this theory probably since the day that article arrived, thirty years ago.

FORBES: Detroit Picks Broken Theory To Fight Crime

Thirty years ago top business schools had a simple philosophy about how to teach students good business leadership.

FORBES