an open question

基本解释

It's an open question: is there such a thing as a "cold constitution"?
這是一個尚未解決的問題：有某種像是“感冒躰質”這類東西嗎？
When or whether the throne will pass to the second generation of Abdul Aziz’s heirs remains an open question.
王位何時，是否會傳到阿蔔杜勒•阿齊玆的第二代子孫仍然是一個公開的問題。
It remains an open question if peanut butter or products with peanut paste would be likely candidates for the technique.
花生醬或含有花生糊的産品是否可能應用這種技術殺菌，這仍然是一個未解決的問題。

I don't believe that markets are efficient and it doesn't really seem like it should be an open question.
我不相信市場是有傚的,而且事實上這似乎,也不應該是一個開放式的問題。
耶魯公開課 - 金融市場課程節選
So here's my attempt to make the question both a bit more precise, and a question that's an open question.
我正嘗試,讓這兩個問題變得更準確,這是個開放性的問題
耶魯公開課 - 死亡課程節選
It's an open question whether you'll believe it when this class comes to an end, but I'd be surprised if many of you believe it now.
即使到課程結束時,能否接受這個觀點,依然是你們的自由,相反,你們要現在就能接受,倒是會讓我感到很奇怪
耶魯公開課 - 心理學導論課程節選

How big a speed bump that will be for each country is an open question.
FORBES: European Economy