If I ever find out who put that stuff in your flask,一旦让我发现是谁在你的酒里下药

find out:发现；找出来；揭发

I must find out which of them was in the right.

我一定要搞清楚他们当中谁有理。

He was at pains to find out the truth.

他尽力了解事实真相。

常用短语:

find out the truth查明真相

find out how the wind blows看风向(观察形势)

find out the hard way经历一番艰苦才学到

Or at least I didn't think I was thinking about it.至少我不认为自己有考虑过

at least:至少

We should brush our teeth at least twice a day.

我们每天应该至少刷两次牙。

think about:考虑；回想

I'll think about it while I have a chew.

我吃饭时会想想看。

Even now when I think about it I feel pain in my heart.

就是现在想起来我心里都感到难受。