Third-person singular simple present indicative form of alter.(verb)
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Use "alters" in a sentence
"As the song rises and falls his expression alters, and when he strikes those stirring chords on the _Kantele_ and speaks of bloodshed and war his whole being seems changed."
"International Revolution does she suddenly awake, her whole expression alters; she reminds one of a beast of prey seeing its victim at hand and preparing to fall upon it and rend it."
"Since my integration, my so called alters (I prefer the term companions) have presented me with the memories they had."