现在，并不是说青铜在当时的希腊很罕见，只是青铜很有价值，容易回收利用。

Now, it is not that bronze was all that rare in Greece then, it is just that bronze was valuable and could easily be recycled.

youdao

的确，从蜗牛身上提取的紫色物质曾经非常昂贵，在当时的社会，只有富人才能买得起。

Indeed, the purple colour extracted from a snail was once so costly that in society at the time only the rich could afford it.

youdao

然而，糙皮病在当时的美洲几乎还不为人所知，甚至在主要以玉米为生的人之间也是如此。

Pellagra was virtually unknown at that time in the Americas, however, even among people who subsisted primarily on maize.

youdao

Where were you? -Sacramento, California, Memorial Auditorium I knew when he was done, this brother is for real.

你当时在哪里？加利福利亚，萨克拉门托的纪念堂,我只知道，这个人非常认真。

普林斯顿公开课 - 人性课程节选

I was quoted in a recent article as "I hated teaching because the students weren't prepared for learning."

在当时的一篇文章中，有人引用我的话,“我讨厌教学，因为学生们总是不做好,预习工作“

普林斯顿公开课 - 人性课程节选

Here's a copy of a letter to Pound by Yeats when they were both living in London.

这有一份叶芝写给庞德的信,他们当时都住在伦敦。

耶鲁公开课 - 现代诗歌课程节选