The use of an unstressed syllable to realize the rhythmic ‘beat’ in a position normally occupied within a metrical verse line by a stressed syllable (see metre). This common device of metrical variation in English verse occurs where an unstressed syllable appears between two other unstressed syllables, or between an unstressed syllable and a line-break. In Keats's line:His soul shall taste the sadness of her might.the syllable of has been promoted to a ‘beat’ position between two other unstressed syllables; this does not mean, though, that it should be heavily stressed in reading aloud. Where promotion occurs on the last syllable of an iambic line, it sometimes produces a weak ending. See also demotion.