She worked silently for some moments, awkwardly with one hand.
Her mouth worked silently for a moment, looking for words.
The two men worked silently for some moments, until the doctor's body was naked on the floor.
His lips worked silently for a moment before he was able to form words.
His mouth worked silently for a few moments before he could manage to speak.
He tried to speak but his throat only worked silently.
He worked silently, putting his whole body into it, glad to be traveling again.
There might be many robots about, but they worked silently.
He turned away while her mouth still worked silently.
His lips worked silently for a moment, and then he said: "Perhaps we should go back now."