这个工厂二十年前就废弃了。

The factory fell into disuse twenty years ago.

《牛津词典》

他二十年前加入了警队。

He joined the force twenty years ago.

《牛津词典》

二十年前建成了一些无障碍设施。

Twenty years ago, some barrier free facilities were built.

youdao

Now, so there's probably a number of people in this room, so when I first started teaching this class 20 years ago, everybody in the room had had chickenpox.

现在,这间教室中的很多人也许,在二十年前,我第一次教这门课的时候,当时教室里的每个人都得过水痘

耶鲁公开课 - 生物医学工程探索课程节选

And,it used to be that twenty or thirty years ago you'd say nothing in France works, and everything works in the U.S, and now it's just the opposite,totally the opposite.

而在二十或三十年前,你会说法国一片混乱,而美国一切运行顺利,现在则恰恰相反,完全相反

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Well, he has a wife whom he loves, Penelope, and he has a son whom he has barely seen because he had to go off to Troy almost 20 years ago to fight that battle and he hasn't been home since.

因为他有挚爱的妻子珀涅罗珀,以及一个由于二十年前,他前赴参加特洛伊战争,而几乎素未谋面的儿子

耶鲁公开课 - 古希腊历史简介课程节选