Derived from the early Petrarchan form, William Shakespeare's sonnets maintain an iambic pentameter however implore an uncharacteristic rhyme scheme and have a final couplet with such strength that the whole character of the form is changed creating a clear thought division between the twelfth and thirteenth line. Shakespeare's style unique sonnet style became, in his time, the predominate English form. However, some poems such as John Keats' On First Looking into Chapman's Homer retained the classic Italian form.(Crowell pg 945) Shakespeare's ....