在这个故事以前，他一直在对自己鼻涕的抗生特性做研究。

Before that he had been researching the antibiotic properties of his own snot.

youdao

这故事一转又回到以前发生的事情。

The story takes a jump back in time.

《牛津词典》

我以前看故事书，现在喜欢看漫画。

I used to read story books but now I like reading comics.

youdao

Well, this is ridiculous because people were making cannons long before 1840.

当然了，这个故事毫无道理,因为人们制作加农炮还是1840年以前的事情了。

麻省理工公开课 - 热力学与动力学课程节选

One of the stories that is often told is the goldsmith banker's story that goes back I don't know how many hundred years.

经常被人们提起的一个故事是,金匠银行家的故事,它可以追溯到,我不知道是几百年以前了

耶鲁公开课 - 金融市场课程节选