一天在上烹饪课的时候。

One day during cooking class.

youdao

在上周的三天里，离开该港口是不明智的。

For three days last week, it was inadvisable to leave the harbour.

《柯林斯英汉双解大词典》

我们努力确保孩子们在上学的第一天不胆怯。

We try to make sure children don't feel intimidated on their first day at school.

《牛津词典》

Now, this is a pretty familiar widget of little gadget that you might see on most websites today, but my God, what an uninteresting problem to solve ourselves.

这是一个大家都很熟悉的小工具,现在在大多数的网站上都可以看到，天哪，如果我们自己解决这样的问题那将是多么无趣！

哈佛公开课 - 计算机科学课程节选

And, you've undoubtedly heard a lot in the public press, and even in the political dialogue such as it is these days that hydrogen might be on environmentally friendly fuel.

毫无疑问你已经在公开新闻上，甚至在政治的对话上听到过了,比如最近这些天,氢气是一种环境友好的燃料。

麻省理工公开课 - 固态化学导论课程节选

Literature, when it says "It is raining," is not looking out of the window, right?

文学上，当说到“天在下雨“时“,并未在同时往窗外看，是吧？

耶鲁公开课 - 文学理论导论课程节选