Third-person singular simple present indicative form of convulse.(verb)
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Use "convulses" in a sentence
"Either way, can't you just see the famous scene from 2035's Oscar-winning film, "When Harry Met Sally at The Korova Milk Bar" -- after a nearby female patron convulses in seizures, an older lady with a blue magnesium wig at the next booth tells her waitress, "I'll have what she's having.""
"Ruthie can feel the licking fire against her bare breasts and stomach as she convulses and vomits."
"The case of Egypt, as it convulses toward becoming a democracy, is similar and at the same time radically different."