beneficial
The definition for beneficial is "Helpful." Used in a sentence: there is no doubt that eating vegetables is beneficial to one's health.
corrective
The definition for corrective is "Intended to correct." Used in a sentence: The school decided to take corrective measures to prevent truancy.
dubious
The definition for dubious is "Questionable." Used in a sentence: Karl found Kevin's claim that he was sick dubious, as he had just seen him playing football.
refurbish
The definition for refurbish is "To brighten or freshen." Used in a sentence: Leeanne cleaned and mended all weekend to refurbish the shabby apartment.
scapegoat
The definition for scapegoat is "Someone who bears the blame for others." Used in a sentence: Audrey used her innocent baby brother as a scapegoat for the missing cookies.