The number of words read from the poem, the so-called four-word poetry, the Cao and Piece. Four words are words sentence is five words a Five-character, Seven is seven characters 1. After the Tang Dynasty, 4 Poems rarely met, so I usually sub-Wu Yan, Seven categories. Five-character ancient classical poems referred to as 5; Seven ancient poetry called Qi Gu; 35 Seven used along with those generally considered Qigu. Five-character verses referred to five laws, limit 8 40 characters; Seven verses referred to Qilu, limited to eight five-set by leaders. More than eight is called long-laws, also known as more than eight lines. Laws are generally long the Cao. Only four are known as quatrains; 5 must total 20 characters, a total of twenty-eight words Superb. Quatrains can be divided into two kinds of law must absolutely and ancient. Tonal metrical law must be subject to the restrictions, not by the tone, the ancient metrical constraints. Ancient absolutely must generally be limited to five.