Phrases and Phrase Endings

Spoken language breathes in sentences, and music breathes in phrases. A phrase is a complete musical thought, usually four measures long, that moves from a starting point toward a harmonic goal. You cannot hear where a phrase ends by watching the melody alone, because melodies often keep moving right through the boundary with a note that ties over or a rhythm that pushes forward. What actually ends a phrase is the harmony underneath: a cadence, a progression that arrives at a point of relative rest. That arrival is the punctuation mark, even when the surface line refuses to stop.

To find phrase boundaries, ignore the melody's rhythm and look for cadence points in the harmony: places where the progression resolves, typically to the tonic or dominant. Mark each cadence, then treat the music between one cadence and the next as a phrase. A sixteen-measure melody with cadences at measures 4, 8, 12, and 16 breaks into four phrases of four measures each, because each cadence closes off the material that came before it and opens a new span.

This is also where the harmony units pay off directly. An authentic cadence, especially a perfect authentic cadence, closes a phrase the way a period closes a sentence: strong, final, settled on tonic. A half cadence or deceptive cadence closes a phrase the way a comma does: it signals a boundary but leaves the ear wanting more. Two phrases joined this way, a comma-phrase followed by a period-phrase, form the next unit up: the period, where phrase endings start working together as a pair.