This is a side of Alan that I never knew existed.

我以前从来不知道艾伦还有这样的一面。

《牛津词典》

I never knew that.

我可不知道这个。

youdao

You never knew, sir, perhaps, that out of doors he never would let himself be taken.

先生，也许你从来就不知道，他是决不会让人把自己带出门的。

youdao

Her lawyer said she never knew that her husband of many years, Juan Lazaro,was really a Russian named Mikhail Vasenkov.

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So that he knew a lot about music, but he never performed or never was active as a musician.

他对音乐很懂，但他从来没有,表演过或者成为一个积极的音乐人。

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But I never knew too much, and my... they don't really speak English that well,

但我知道的不多，而且我的。。。实际上他们的英语并不是很好。

学习外语的原因 - SpeakingMax英语口语达人

Can you be a hero for beating an illness that we never knew existed?

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Her neighbors seemed largely sympathetic, noting that Bernardo's only sister died young and that she never knew her father.

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Visiting these places was like finding an extra room in your apartment that you never knew was there, a sort of miracle.

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