but I have to stay and find out what else they know about that night.可我必须留下看看他们对那晚还知道些什么

find out:发现；找出来；揭发

I'd like to find out about train to Las Vega.

我想知道去拉斯维加斯的情况。

You can find out many advantages in urban life.

你会发现都市生活中有许多便利之处。

what else:还有什么

I'd like to know what else needs clarifying.

我想知道还有什么需要澄清。

Oh, Jenna just said she's about to leave,詹娜说她马上要走了

be about to:刚要； 即将

I am about to jump out of my skin.

我吓得心要跳出来了。

She was about to dish up when some guests came.

她刚要上菜开饭，这时来了一些客人。