一无所知

He may be rich for aught I know.

他也许有钱但我所知。

This might seem very perplexing to those who know nothing about it.

这对那些对它所知人来说可很难理解。

I regret my ignorance on the subject.

我很遗憾, 对此问题所知。

He displayed a willful ignorance of their plight.

对于他们困境他故意装作所知。

We are still woefully ignorant of the causes of this disease.

不幸是，我们仍对这种疾病致病原因所知。

I hasten to add that I knew nothing of the fraud at the time.

我忙不迭地补充说，我当时对那个骗局所知。

He was a little vague when I asked what had happened.

我问他出了什么事时，他所知。

He closed up when he found he knew practically nothing about the subject under discussion.

当他发现自己对所讨论问题实际上所知时, 就不再开口了。

As I opened up the computer to try and fix the problem, I realized that I was getting into completely uncharted waters and considered whether to leave it to the experts.

当我打开电脑打算修理它时，我意识到这是个自己所知领域，于是我考虑要不要请专业人员帮我解决。