Like many postmodern poems, and Heaney’s in particular, “Punishment” does not use a specific rhyme or meter. However, “Punishment” does utilize elements of sound and set stanzaic and line lengths. The poem is broken into four-line stanzas, or quatrains. Quatrains are notable for their connection to ballads and other musically-inclined forms of poetry or verse. Heaney’s use of quatrains is modernized by a lack of set rhyme and a focus on sound movement.

Rather than the lines ending on specific sounds or end-rhymes, “Punishment” is notable for its use of internal rhyme and onomatopoeic properties. The poem is heavy on long, internal vowel sounds, giving the piece a sense of doom, fear, or pain. For example, the repeated long vowel sounds of "drowned" (Line 9), "body in the bog" (Line 10), "stone" (Line 11) and "floating rods and boughs" (Line 12) of the third stanza. The long vowels are reminiscent of a keening, wailing, or howling. The line lengths are all roughly the same, with almost every line possessing between three and six beats. The poem itself is broken into 11 stanzas, which mathematically implies a sense of constancy or continuance.