There are actually three words to distinguish here. “Recent,” always pronounced with an unvoiced hissy S and with the accent on the first syllable, means “not long ago,” as in, “ I appreciated your recent encouragement.” “Resent” has two different meanings with two different pronunciations, both with the accent on the second syllable. In the most common case, where “resent” means “feel annoyed at,” the word is pronounced with a voiced Z sound: “I resent your implication that I gave you the chocolates only because I was hoping you’d share them with me.” In the less common case, the word means “to send again,” and is pronounced with an unvoiced hissy S sound: “The e-mail message bounced, so I resent it.” So say the intended word aloud. If the accent is on the second syllable, “resent” is the spelling you need.
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