The number of words in each sentence is equal. (Five or seven words) 3: Finally, the rhyme must be flat. (A) rhyme, modern poetry can not rhyme. B, even sentences must rhyme, the first sentence can rhyme or not, and odd sentences don't rhyme. C. The rhyme of the first sentence is the positive case, and the non-rhyme is the variant case. The five laws take the first sentence as the positive case without rhyme, and the rhyme as the change. ) 4: Pairing in the middle (first connection, parallel connection, neck connection and tail connection, which means that parallel connection and neck connection must be paired. Generally speaking, neck joints need a pair of workers, and parallel joints can be wide pairs. The first couplet and the last couplet may or may not be couplets, but they should not both be couplets. Another variant is couplets, which are not couplets, called stealing spring style. 5. Conform to the parallel style (that is, it must conform to the rhythm of poetry)