It won't be long before we know the result of the experiment.

不久之后，我们就会知道实验的结果。

youdao

Before we know it, we're thankful for negative things, too.

不知不觉中，我们也会对消极的事情心存感激。

youdao

It will be two years before we know whether it is effective.

两年之后我们才能知道它是否有效。

youdao

It is a slippery slope. And, we're not careful, before we know it all of us will be in a much more dire situation."

VOA: standard.2009.11.11

So this means we can actually calculate this for any molecule that we've drawn the Lewis structure for, because we actually do need to draw the Lewis structure before we know, for example, how many of each of these we have, or at least go through the rules.

这意味着我们可以将原来画过,路易斯结构的分子的形式电荷计算出来，因为我们其实在画出,路易斯结构之后才能知道，比如，这些量的值是多少，或者至少我们需要经过前面的那些步骤。

麻省理工公开课 - 化学原理课程节选

And he actually did this in the late 1800's, back before even all of the elements that we know today were discovered, really only about 60% or so, 70% were discovered then that we now know today.

他最终在十九世纪晚期完成了这一壮举，难能可贵的是,虽然我们现在已经发现了所有的元素，但在当时已知的元素只有我们现在知道,百分之六七十，在这种情况下。

麻省理工公开课 - 化学原理课程节选

It will be at least a few years before we know whether any of these treatments help.

FORBES: Twilight Zone

"We'll be in the midst of it before we know it, " Belshe said.

CNN: School: No shortage of volunteers for swine flu vaccine trials

There may be more involved, but we'll have to wait before we know just how serious the move could be.

ENGADGET