Poetry have challenged the traditional definitions of the sonnet form, rendering entire sequences of "sonnets" that often lack rhyme, a clear logical progression, or even a consistent count of fourteen lines. "Shi" () Is the main type of Classical Chinese poetry. Within this form of poetry the most important variations are "folk song" styled verse ("yuefu"), "old style" verse ("gushi"), "modern style" verse ("jintishi"). In all cases, rhyming is obligatory. The Yuefu is a folk ballad or a poem written in the folk ballad style, and the number of lines and the length of the lines could be irregular. For the
Sonnet 90 other problems will pale into insignificance. Sonnet 90 is an English or Shakespearean sonnet. The English sonnet has three quatrains, followed by a final rhyming couplet. It follows the typical rhyme scheme of the form, "abab cdcd efef gg" and is composed in iambic pentameter, a type of poetic metre based on five pairs of metrically weak/strong syllabic positions. The 10th line exemplifies a regular iambic pentameter: Lines 5 and 7 have a final extrametrical syllable or "feminine ending". Line 7 may also be read as exhibiting another common metrical variation, the initial reversal: Initial reversals also occur in lines