The definition for commemorate is "To mark by a ceremony." Used in a sentence: Each year, the Franklins commemorate their anniversary by visiting the site of their first date.

The definition for insolence is "Boldness or rudeness." Used in a sentence: The boy's insolence to the policeman embarrassed his mother.

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

The definition for refurbish is "To brighten or freshen." Used in a sentence: Leeanne cleaned and mended all weekend to refurbish the shabby apartment.

The definition for untenable is "Not able to be defended." Used in a sentence: Rashid made the untenable statement that George Washington was the second president of the United States.