As for Common, Plain Chant, and High Chant: Common is ordinary speech, of course; telling a story as one man in the street might tell another. Plain Chant adds a rhythmic half-singing to poetic imagery; nothing is ever described plainly; conveying emotion is as important as conveying description. High Chant is sung, really, as though Benedictine monks had been brought up in a tradition of Chinese music; the rhythms are more precise, and emotional content is more important than mere description. High Chant can be all but unintelligible to those who are not used to it; it is a form used only by court bards and the like. I should point out that Common, Plain and High are not language names, but names used by bards for different forms of recitation.
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