The melody of the Polish anthem is a lively and rhythmical mazurka. Euphony is the effect of sounds being perceived as pleasant, rhythmical, lyrical, or harmonious. In poetry, the caesura is used to diversify rhythmical progress and thereby enrich accentual verse. This causes them to fire impulses which stimulate rhythmical contraction and relaxation, called peristalsis. All compositions are characterized by a subtle and fluent rhythmical arrangement. "I Bleed" is melodically simple, and is formed around a single rhythmical repetition. It is used for rhythmical accompaniment during dances, soloist or choral singing. The thematic idea (main melody or rhythmical groove) comes first. The spinal cord executes rhythmical and sequential activation of muscles in locomotion. Students who enjoy sound, rhymes, and music are musical/rhythmical learners. Duck uses a unique fighting style which includes rhythmical dance-like movements and attacks. The song features strings and flute instrumentation with a rhythmical chorus. Its metres, too, are more obviously rhythmical than the stylised classical metres. Principally a literary term denoting a rhythmical pause and break in a line of verse. These are replaced by other features such as stress and rhythmical variations.