That's news to me.
对我来说可是新鲜事
I've never heard of that.
我从没听说过
I did not know that.
我不太了解
I had not been informed of that.
我没有被通知这件事

想要开始怎么说？
Let's start.
开始吧
Let's get started.
开始吧
Can we get started now?
我们能开始了吗

Speak of the devil
说曹操曹操到
Old superstition
古老的迷信
Speak of the devil, and he will be at your elbow.
说曹操曹操到。