I 'll never know what, made you run away.

我永远不会知道，是什么让你离开。

youdao

How it got into my pajamas I'll never know."

至于它怎么进来的,我就不知道了"

耶鲁公开课 - 心理学导论课程节选

I'll never know because I still value the functioning ability of my esophagus.

CNN: Apparently This Matters: World's hottest curry

I'll never know 100 per cent whether it was a detective, but I have my suspicions.

BBC: India's 'wedding detectives' enjoy booming trade

But what it was like spending months locked up behind barbed wire, I hope I'll never know.

BBC: Tom Conti: My dad, sent to a prison camp for being Italian