talk quietly in a negative way 英語で:

Don't mutter to yourself, if you have something to say - say it out loud!

Ron muttered, “Show-offs.”

Dory kept muttering the address.

Stop muttering and speak up! / ‘How dare she,’ he muttered under his breath.

He muttered to himself as he walked.

She walked past me, muttering to herself.

The woman muttered an answer.

One of the skaa muttered uncomfortably.

Whenever the waiter walks by, cough and mutter, “No tip tonight buster"

Lucas was muttering under his breath because he was angry at his girlfriend.

I didn't understand his mutter.

Laurence muttered something about his wife and left.

mutters something under his breath,