1. Different sources: quatrains come from the ballads of the Han, Wei, Southern and Northern Dynasties. After the Tang Dynasty, quatrains in the near aspect prevailed, and the meter was the same as the first, last or middle four sentences in eight metrical poems. Therefore, some people in the Tang Dynasty attributed quatrains to metrical poems in their poetry collections.
Metric poems originated from Shen Yue and other new-style poems that emphasized the antithesis of metrical poems in the Southern Dynasties, and were further developed and stereotyped by Shen Quanqi and Song Wenzhi in the early Tang Dynasty, which prevailed in the Tang and Song Dynasties.
2. Different classification and requirements: quatrains are also called sentence cutting, sentence breaking and quatrains. Every four sentences, metrical requirements are not as strict as metrical poems, and they are generally five or seven words. Known as the five wonders, seven wonders, and occasionally six wonders.
The rhythm is rigorous, and the number of words in the poem is required to be unified. Every poem is a sentence with five words, six words and seven words, which are referred to as five words, six words and seven words for short, of which six words are rare.
3. The number of sentences is different: quatrains stipulate four sentences for each poem, while ordinary metrical poems stipulate eight sentences for each poem. If there are only six sentences, it is called a small law or a three-rhyme poem; More than 8 sentences, that is, 10 sentences, are called exclusive laws or long laws.
4. Different rhymes: rhyming requires the whole poem to have rhyme, and the rhyme is limited; The second, fourth, sixth and eighth sentences rhyme, the first sentence can be put on or off, and the words of each rhyming sentence are flat. There are "flat rise" and "flat rise" in the upper and lower sentences. In addition, the metrical requirements of metrical poems also apply to quatrains, but the level and level of quatrains are not as strict as metrical poems.