In for a penny, in for a pound.

一不做 二不休。

Oh well, it’s done now. In for a penny, in for a pound.

【penny】哎呀，现在干完了，有始有终嘛。

If there's anything queer about him when we once get into the work; in for a penny, in for a pound.

如果我们一旦开始工作，他有什么古怪之处；一分钱，一英镑。