His boastful accents died away into a mumble: "Dunno what I should do."
I understood his mumble to mean that "he didn't know any game."
He squeezed my arm till he extorted from me some sort of mumble.
Gone was the mumble, gone was every thought except the misery of the minute.
When he would cry out to her his frozen lips could mumble no words.
The trader, half dead ...