It only lasted a couple of years, as far as I know.

据我所知，它仅维持了几年。

《柯林斯英汉双解大词典》

Human curiosity demands that we know actual age in years.

人类的好奇心驱使我们了解实际年龄。

youdao

I know that you've been studying chimpanzees for thirty years now.

我知道你研究黑猩猩至今已有30年了。

《柯林斯英汉双解大词典》

Scientists know that some of the Bristlecone pines in northern California are also more than four thousand years old.

VOA: special.2009.05.12

But it was there for over a thousand years, and we now know things to be a little different.

但是，它存在了超过1000年，我们现在知道的事情有点不一样。

麻省理工公开课 - 固态化学导论课程节选

So it was like a big shock to me because after five years, I thought I know the language.

所以，这对我来说，就是一个很大的打击，因为五年的学习以后，我以为我掌握这门语言了。

语法和语调是关键 - SpeakingMax英语口语达人

As middle-class Americans who have seen their real incomes decline in the last four years know, that's a huge number.

WSJ: Review & Outlook: The Immigration Windfall

Accountants who audit a company for years know more about it, says Don Moore, a psychologist at the University of California, Berkeley, who has studied conflicts of interest.

WSJ: The Intelligent Investor: One Cure for Accounting Shenanigans

Now, those of us who have been paying any attention at all for the past few years know that savvy men no longer aspire to be the Marlboro Man, but rather someone like Barack Obama or Brad Pitt.

FORBES: Can Men Really Be An Endangered Species?