beneficial
The definition for beneficial is "Helpful." Used in a sentence: there is no doubt that eating vegetables is beneficial to one's health.
demean
The definition for demean is "To lower status." Used in a sentence: The embarrassing photograph demeaned the candidate in the eyes of the voters.
genial
The definition for genial is "Sympathetic, friendly." Used in a sentence: The genial host warmly greeted his many guests.
interminable
The definition for interminable is "Never ending, or seemingly endless." Used in a sentence: The impatient Zoe found the longwinded lecture interminable.
revoke
The definition for revoke is "To cancel by taking back." Used in a sentence: After Kal's father revoked his allowance, he had no money for the movies.