The first fifty years are the hardest.

最初的五十年是最艰难的。

youdao

Thus the first fifty years may be characterized as our learning about the limits of our field, which are intimately bound up with the limits of complexity with which humans can cope.

于是，可以说刚开始的五十年我们都是在学习软件领域的这些限制，这些限制主要跟人类所能应付的复杂性有关。

youdao

If he wins—and it's a big if —he'll be the first Englishman to win for fifty years.

假设他赢了—不过这还是个很大的疑问—他将成为五十年以来第一个获胜的英格兰人。

《牛津词典》

The collision of the Russian and American satellites was the first of its kind in over fifty years of space travel.

VOA: special.2009.04.01

But her trip to Japan,Indonesia,South Korea and China makes her the first in almost fifty years to visit Asia first.

VOA: special.2009.02.21

The work was first performed in Germany in two thousand to mark two hundred fifty years since the death of the composer Johann Sebastian Bach.

VOA: special.2010.07.19

For roughly the first half of the past fifty million years, the region lay beneath a warm, shallow sea.

NEWYORKER: Bones of Contention

For the first time in fifty years my country is preparing for war.

BBC: Is the UK government right to deploy British troops?

For the first time in more than fifty years, Cuban citizens can travel abroad without permission from their government.

FORBES: It's Time For The U.S. To End Its Senseless Embargo Of Cuba