I'll try if I know all the things I used to know.

如果我知道所有我过去知道的事情，我会试一试。

youdao

I'm damned if I know who he is.

我根本不认识他。

《牛津词典》

I'm surprised they've invited me to their wedding—it's not as if I know them well.

我很惊讶他们居然请我参加他们的婚礼—我跟他们似乎并不熟。

《牛津词典》

But we certainly didn't have goals. I don't know if we had ever heard of Grammys at that point.

VOA: special.2010.04.19

It's very simple. It's this: if I know what I'm doing, it is almost inevitably the case that you would know also.

实际上十分简单：,如果我知道我创作的是什么，那么你很可能也知道我创作的内涵。

普林斯顿公开课 - 人性课程节选

It's called, I don't know if you guys speak any Japanese, but it's called Bungo, the thing that we're focusing on.

我不知道你们是否会日语，但我们主要学习的东西被称作“豊后”。

最喜欢的一门课 - SpeakingMax英语口语达人

If I know where you are, I should be able to give you a better experience.

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"If I know there's an approaching storm, I will stay here, I'll sleep in the restaurant, " he said.

WSJ: 'Because God Says So'

"If I know there's a trophy here, I can sit forever, " he says, motioning to a small bucket that serves as a Port-O-John.

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