他们曾观察过这些动物的习性。

They had observed regularities in the behaviour of the animals.

《牛津词典》

他们曾赢过前几起与政府的工资纠纷。

They have won previous pay disputes with the government.

《柯林斯英汉双解大词典》

他们曾密切合作，共同规划这一项目。

They had cooperated closely in the planning of the project.

《牛津词典》

There may even be people here who distinguished themselves because they starred in Romeo and Juliet. Or, maybe they produced.

这间教室里甚至有人,才华横溢，因为他们,曾在罗密欧与朱丽叶中演出，或者他们是制作人。

麻省理工公开课 - 固态化学导论课程节选

We know their dream; enough ; To know they dreamed and are dead; And what if excess of love Bewildered them till they died?

我们知道他们的梦,他们曾梦过，死了;,在他们死前就算过多的爱,曾使他们困惑，又怎样呢？

耶鲁公开课 - 现代诗歌课程节选

And we learn about the maternal grandparents, the paternal grandparents, and the brothers and sisters, aunts and uncles, and what each one of them did.

我们学习了外祖父母，祖父母，兄弟姐妹，叔舅姨姑，还有他们曾做过什么。

麻省理工公开课 - 媒体、教育、市场课程节选