Now you're not supposed to know any of this.

现在你一窍不通都完全正常

耶鲁公开课 - 聆听音乐课程节选

But she's a horrible singer and dancer.

但她对唱歌和跳舞实在是一窍不通。

Who 实战 - SpeakingMax英语口语达人

As you can see I don't understand it.

你看得出来我对此一窍不通

耶鲁公开课 - 古希腊历史简介课程节选

I don't understand anything about cars.

我对汽车一窍不通。

I'm ~ing 实战 - SpeakingMax英语口语达人