There are various forms of Tang poetry. There are basically two kinds of ancient poems in Tang Dynasty: five-character poems and seven-character poems. There are also two kinds of modern poems, one is called quatrains, and the other is called metrical poems. Quatrains and metrical poems are five words and seven words respectively. Therefore, there are basically six basic forms of Tang poetry: five-character archaic poetry, seven-character archaic poetry, five-character quatrains, seven-character quatrains, five-character rhythmic poems and seven-character rhythmic poems. Classical poetry has a wide range of requirements for rhyme and meter: in a poem, the number of sentences can be more or less, the chapters can be long or short, and the rhyme can be changed. Modern poetry has strict requirements on rhyme and meter: the number of sentences in a poem is limited, that is, four-line quatrains and eight-line meter poems. The words used in each poem have certain rules, and the rhyme cannot be changed; Rhyme also requires that the middle four sentences become antithesis. The style of ancient poetry is handed down from the previous generation, so it is also called ancient style. Modern poetry has strict rules, so some people call it metrical poetry.