Sonnet 30 up of fourteen lines in three quatrains and a couplet, rhyming "abab cdcd efef gg". While using the rhyming and metrical structure of the 'English' or 'Surreyan' sonnet, Shakespeare often also reflected the rhetorical form of the Italian form also known as the Petrarchan sonnet. It divides the sonnet into two parts: the "octet" (the first eight lines) usually states and develops the subject, while the "sestet" (the last six lines) winds up to a climax. Thus a change in emphasis, known as the "volta", occurs between the end of the eighth and the beginning of the ninth lines —
Poetry sonnet), Michael Drayton, and Shakespeare, whose sonnets are among the most famous in English poetry, with twenty being included in the "Oxford Book of English Verse". However, the twists and turns associated with the "volta" allow for a logical flexibility applicable to many subjects. Poets from the earliest centuries of the sonnet to the present have utilized the form to address topics related to politics (John Milton, Percy Bysshe Shelley, Claude McKay), theology (John Donne, Gerard Manley Hopkins), war (Wilfred Owen, e.e. cummings), and gender and sexuality (Carol Ann Duffy). Further, postmodern authors such as Ted Berrigan and John Berryman