如果曾经没有焦虑和苦恼过，我们本身是不会去自寻烦恼的。

We ourselves cannot then enter into the anxiety and anguish which we had before conceived.

youdao

如果曾经使用过这些工具，就会注意到通常想法并不总是不经意间产生的。

If you used these tools, however, you may have noticed that often thoughts aren't so random.

youdao

如果曾经使用HTML编写过表的话，理解表对象的基础就会容易些。

If you've ever written a table using HTML, it will be easy for you to understand the basics of a table object.

youdao

If it ever did have an author's name attached to it, we don't have any evidence in the manuscript history.

如果它曾经写有作者的名字，那么原始手稿里没有任何证据。

耶鲁公开课 - 新约课程节选

But if you want to know the answer, and I knew it, but I forget what it is-- it doesn't matter.

如果你想知道答案,我曾经是知道答案的,不过我忘掉了,这不重要

耶鲁公开课 - 心理学导论课程节选

To be honest, especially those of you less comfortable here, if you've ever struggled with some program or struggled with some piece of software, oh it's alright, it's not your fault.

说实话，尤其是对那些在这里上课有些吃力的同学，如果你曾经使用哪个程序或软件有困难,好吧，那不是你的错。

哈佛公开课 - 计算机科学课程节选