What I know now is that feelings are really your GPS system for life.

我所知道的就是你的内心是你人生的导航系统。

youdao

If I had known then what I know now, I probably would have done things differently.

如果当时我知道现在的情况，可能我就不会那样做了。

youdao

The only thing I would change, if I knew then what I know now, is to make that warning louder, because back in 1997-98 nobody listened.

如果我以前知道现在所知道的东西，那么我要修改的唯一的东西是使警告更大声一点，因为在 1997 - 98 年，没有人会听进这些警告。

youdao

"A player who hasn't been playing for very long, I try to keep them next to the section player, or leader as we call it, that has been playing a while so they can always ask questions say, 'Hey,I don't know what that means.'" Matt is now in college, studying music education.

VOA: special.2010.06.21

So I think that's interesting that now they are thinking what they know and they are learning something different.

孩子们现在回想,他们熟悉的事物,同时学习一些新的知识。

麻省理工公开课 - 媒体、教育、市场课程节选

That didn't happen to me -- once I got into the lab, I didn't want to leave. So, I thought, "You know what, I think I'll change the medical school plans and now I'm going to go all the way -- chemistry major, chemistry grad school."

这很好，但我不是这样，我一进入到实验室就不想离开了，所以我想“你知道吗,我想把我学习医学的计划改成化学-,我要学化学专业，读化学研究生“

麻省理工公开课 - 化学原理课程节选

Mr. CHERTOFF: If I'd known then what I know now about Mr. Brown's agenda, I would've done something differently.

NPR: House Report on Katrina Details Critical Response Flaws

If I knew then what I know now, I would have had to have included a discussion about air quality.

FORBES: Air Quality In China

You know, I've said many times if I had known then what I know now, I never would have given President Bush the authority.

CNN: Transcript of Thursday's Democratic presidential debate