The definition for benefactor is "One who offers financial help." Used in a sentence: Michael's aunt and benefactor paid his college tuition.

The definition for beneficial is "Helpful." Used in a sentence: there is no doubt that eating vegetables is beneficial to one's health.

The definition for corroborate is "To support with evidence." Used in a sentence: "Unless you can corroborate your story, it will not be admissible in court," the attorney told his client.

The definition for corrosive is "Bitingly sarcastic." Used in a sentence: The cruel Estella's corrosive comments made Pip cry.

The definition for moderate is "Tending toward the average." Used in a sentence: The best–selling writer was disappointed; his new novel was only a moderate success.