Just leave him at his psychohistory and he'll mumble quietly to himself for the rest of his life.

"I'll make sure," Barbousse said, then quietly mumbled a few unintelligible phrases into a blood-smeared ear.

They mumbled quietly, then grew impatient.

I stopped leafing through the book and my eyes followed my finger down the text while I quietly mumbled to myself.

As the piece continues, John quietly mumbles "Gonna be alright" a few times.

I just wanted to go out and play well," O'Neal said, mumbling quietly into a microphone as he quickly dressed after the game.

They are generally very calm birds and typically mumble quietly, and their calls are not high-pitched or piercing to the ear.

Califone's songs shuffle along and quietly mumble to themselves, never rushing or raising their voices as they create an aura of down-home mystery.

A punk rocker quietly mumbled "Grateful Dead," the arch enemy of the loud/ fast/hardcore movement.

Athelstan stared round at the rest, mumbling quietly like people who wanted to maintain appearances though he sensed their tension.