要是我们预先知道这事就好了。

I wish we'd known about it beforehand.

《牛津词典》

她如何预先知道我将出门的？

How could she tell beforehand that I was going to go out?

《柯林斯英汉双解大词典》

要是她事先知道会有什么遭遇的话，她是决不会同意去的。

If she had known what lay in store for her, she would never have agreed to go.

《牛津词典》

What I thought I would do is first give you a little bit of sense of some of the opportunities that we as a group have been exploring.

我想我先要做的是给你们,一点感觉，知道我们这个团队,是研究什么的。

麻省理工公开课 - 媒体、教育、市场课程节选

So on the one hand--temporal sequence-- first you know Ruth, you meet Ruth, you get to know Ruth.

所以一方面,按时间顺序来说,你需要先知道露丝,见到露丝 了解露丝

耶鲁公开课 - 死亡课程节选

It's just a placeholder that says I don't yet know what I wanna put here but I wanna put something, let me get back to you in just a moment.

它只是一个占位符，告诉电脑,我想在这放一个东西，但是暂时还不知道放什么东西，我先打断一下。

哈佛公开课 - 计算机科学课程节选