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 flourish is "To make bold, sweeping gestures." Used in a sentence: The fairy godmother flourished her wand and turned the pumpkin into a carriage.

The definition for frugal is "Thrifty, cheap." Used in a sentence: The frugal shopper only bought items that were on sale.

The definition for genial is "Sympathetic, friendly." Used in a sentence: The genial host warmly greeted his many guests.

The definition for periodic is "Occurring at regular intervals." Used in a sentence: The periodic innterruptions of the cuckoo clock prevented Li from concentrating.