apathetic
The definition for apathetic is "Showing little or no emotion." Used in a sentence: Carmine was concerned about his usually cheerful brother's apathetic attitude.
elate
The definition for elate is "To fill with joy." Used in a sentence: It elated Margaret to be awarded first place in the science fair.
incumbent
The definition for incumbent is "Necessary as a duty or responsibility." Used in a sentence: It was incumbent on Jack to attend his father's retirement party.
interminable
The definition for interminable is "Never ending, or seemingly endless." Used in a sentence: The impatient Zoe found the longwinded lecture interminable.
procrastinate
The definition for procrastinate is "To put off intentionally." Used in a sentence: Yvonne's father urged, "Don't procrastinate. Clean your room right away."