I don't know. Correction—I do know, but I'm not going to tell you.

我不知道。不，我知道不假，但不打算告诉你。

《牛津词典》

I do know how upset the shop staff can get, but I try to persuade them to keep smiling.

我知道店员会有多生气，但我努力说服他们保持微笑。

youdao

I don't know the words to a lot of songs, but I do know some folk songs that my grandma taught me at an early age.

我不知道很多歌的歌词，但知道一些我奶奶小时候就教会我的民歌。

youdao

As much as I don't look forward to it, I do know that I'm going to have to."

VOA: standard.2010.03.18

But I do know this.

但我知道。

耶鲁公开课 - 死亡课程节选

And I do know, as I have worked as a publicist, that people do, celebrities do call paparazzi

而且我也知道，因为我曾做过宣传的，有的人，名人，确实会给狗仔队打电话，

溺爱是一种伤害 - SpeakingMax英语口语达人

What I do know is that it will have to keep innovating to keep that valuation.

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But I do know that all countries really want the resolution part of this.

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What I do know is that the law is horrible, and the IRS is immoral.

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