Игра слов в оригинале звучит так: 'Yes, I realize you’ve got to say that, sir. Walls have ears, sir. Mum’s the word. But we all had a talk, and we reckoned you’ve been very good to us, sir, you really believe in the Post Office, sir, so we thought: it’s time to put our money in our mouth, sir! said Groat, and now there was a touch of defiance.

Moist gaped once or twice. 'You mean "where your mouth is"?.