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 exasperation is "The state of being irritated." Used in a sentence: The longer Jorge waited in line at the ticket counter, the more his exasperation grew.

The definition for facade is "false or superficial appearance." Used in a sentence: Emily's smile is just a facade masking her broken heart.

The definition for obnoxious is "Highly offensive." Used in a sentence: The manager asked the obnoxious diner to leave the restaurant.

The definition for repentant is "Feeling regret." Used in a sentence: The repentant Dana admitted to cheating on the test.