When people speak vehemently, they are expressing their opinions or feelings with intense passion and energy. Synonyms for this phrase include "argue heatedly," "protest loudly," "vehemently assert," "passionately assert," "vociferously argue," and "forcefully articulate." Other synonyms include "rant," "rave," "rail," "shout," "yell," and "scold." These words are often used to describe someone who is angry or frustrated with a situation and is speaking passionately about it. Whether in a personal or professional setting, speaking passionately can be a powerful way to convey one's thoughts and feelings, but it is important to do so in a respectful and civil manner.