Do any of the sonnets depart from the standard Shakespearean sonnet form?
There are at least two major deviations from standard Shakespearean sonnet form among the 154 pieces now grouped under the heading of Shakespeare's Sonnets. Sonnet 126, the last in the "young man" cycle, has only twelve lines instead of the conventional fourteen. Sonnet 145 is composed in tetrameter, rather than the conventional pentameter. In addition, the last two pieces, Sonnets 153 and 154, are at complete odds with their predecessors. They are plainly variations on well-known epigrams that Shakespeare was familiar with from ancient Roman literature and probably drew from Ovid's Metamorphosis.