It would be good to take a look at

It would be good to take a look at the structure of the Petrarchan Sonnet. Petrarchan sonnets have 14 lines and two parts. The first part is called the octave and its rhyme scheme is: abbaabba. The second section has six lines and is called a sestet. The rhyme scheme in the sestet is flexible to a point. Two or three rhyme patterns may be arranged in different ways. But the last two lines may never be a couplet. This differs from the Shakespearean sonnet, which always ends in a couplet and has 12 lines. In spite of the strict Petrarchan form, however, Spenser seems to have created his own blend between the two types of sonnets.