v.mutter ; move one's lips silently ; move the lips and mouth silently ; jerk ; twitch ; pucker and slacken alternatingly
เขายังขมุบขมิบปากอยู่เลย ทั้งที่ไม่มีอะไรจะพูด
He was still muttering and moving his lips silently, even though there was nothing to say.