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 —
Sonnet 16 'sow' it (compare Sonnet 15 where it is used of grafting) so that it can give birth to the youth's "living flowers," self-generated new copies. Interpretation of the sonnet is said to hinge on the third quatrain (lines 9-12), which is generally regarded as obscure. Edmond Malone suggested that "lines of life" refers to children, with a pun on line as bloodline. This reading was accepted by Edward Dowden and others. Also, "repair" can mean to make anew or newly father (re + père), which may be relevant. But as well, "lines of life" can mean the length of life,