His expression fell, as if he'd never thought of it quite that way.

His face was a bitter mask of hatred, and the emotionless expression fell away.

A resigned expression fell across the face of the man in green.

Peter saw it, and his expression of calm reassurance fell away.

Kirk glanced at the princes, and saw their expressions fall.

A dour expression has now fallen Ji over his face.

His expressions of repugnance at the entire plan had fallen on too many deaf ears.

An expression of great agony and sorrow fell over the swordsman's face.

Whether a given expression has fallen into this category is a matter of opinion.

The expression has fallen out of use by young African-Americans today.