beneficial
The definition for beneficial is "Helpful." Used in a sentence: there is no doubt that eating vegetables is beneficial to one's health.
comprehensible
The definition for comprehensible is "Understandable." Used in a sentence: Shannon spoke slowly so her directions would be comprehensible to her foreign visitor.
duplicity
The definition for duplicity is "Deceptive thought, speech, or action." Used in a sentence: The life of an undercover detective is filed with necessary duplicity.
equitable
The definition for equitable is "Fair and equal." Used in a sentence: The judge made an equitable decision dividing the estate evenly among the sisters.
melodious
The definition for melodious is "Having a pleasing melody." Used in a sentence: The melodious sounds of the symphony soothed Tim after his trying day.