彼は忘我の境地で絵筆を走らせていた。
He was moving his brush in a state of complete self-forgetfulness.
観客は忘我の表情で演奏に聴き入っていた。
The audience listened to the performance with rapt, entranced expressions.
祭りの太鼓に合わせて、人々は忘我のうちに踊り続けた。
To the beat of the festival drums, people kept dancing as if in a trance.