The rhyme is constructed of quatrains in trochaic tetrameter catalectic, (each line made up of four metrical feet of two syllables, with the stress falling on the first syllable in a pair; the last foot in the line missing the unstressed syllable), which is common in nursery rhymes. In its most common form it relies on a double repetition, rather than a rhyming scheme, which is a frequently employed device in children's rhymes and stories. The Roud Folk Song Index, which catalogues folk songs and their variations by number, classifies the song as 502.