这位教授做了详尽的研究在写这篇文章之前。

The professor did exhaustive research before writing this article.

youdao

本应该两星期之前开始写这篇文章，而事实上我现在才开始。

I should have started this article two weeks before I actually did.

youdao

我本该在很久之前就写这篇文章。

I should have written this post a long time ago.

youdao

我本该在很久之前就写这篇文章。

I should have written this post a long time ago.

youdao