youdao

She had known Max for some years now, but he was still pretty much an unknown quantity.

她现在认识马克斯也好几年了，但是他仍然是个大大的未知数。

《柯林斯英汉双解大词典》

My wallet was gone. I could only have left it on the G9 bus, which was now speeding in the dark to some unknown station.

我的钱包不见了。我只能把钱包留在 G9 公交车上，如今，那辆公交车正在黑暗中飞速驶向某个未知的车站。

youdao

But now she is on her own, "with no direction home, like a complete unknown, like a rolling stone."

VOA: special.2009.06.21

American government policy is the great unknown now.

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Henry Lockwood of Western New York is among them, unidentifiable in death and his burial location unknown until now.

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What comes after that is an unknown right now.

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