But then his mouth moved and he said something I couldn't hear.

Her mouth did not move but the words became part of the night.

Her mouth moved, as if to ask a question, but no sound came out.

Her mouth was moving, but no words were coming out.

His mouth moved again, but she still could not hear him.

His mouth moved a little, but no sound came out.

She looked at him, her mouth moved, but no words came out.

Though the mouth moved, the voice was not coming from it.

Her mouth didn't move so well at one side now, after that last turn.

I walked around to his back, and the mouth moved to the front.