The definition for appraise is "To evaluate the worth of." Used in a sentence: Simone, an expert in African sculpture, was asked to appraise the ambassador's collection of masks.

The definition for diffident is "Lacking self–confidence." Used in a sentence: The diffident student never raised her hand in class, even when she knew the answer.

The definition for repel is "To resist, reject." Used in a sentence: The soldiers made a massive charge to repel the invaders.

The definition for servile is "Fearfully submissive." Used in a sentence: Felicia's servile attitude annoyed her boss, who preferred an assistant with more backbone.

The definition for stern is "Harsh, severe." Used in a sentence: The stern principal canceled the prom after the seniors played a silly prank.