你真的不明白他们究竟是谁、想要做什么，也不知道是不是真的对他们有感觉。

You really have no idea who they are and what they're about or if you have any chemistry.

youdao

我没有感觉到有什么其他药物问题，我知道除了充血问题，还有尿疗的效力对我不是立即明显。

I don't really have any other medical problems that I'm aware of other than the congestion thing, so the effectiveness of UT might not become immediately obvious to me.

youdao

Think about what it's like to see red, the sensation of seeing red.

想一想,看见红色有什么感觉,对红色的知觉是什么样的

耶鲁公开课 - 死亡课程节选