Are there any rules for writing ancient poems?

Poetic style as opposed to modern poetry. Before the formation of modern poetry, all kinds of poetry genres except Chu Ci. Also known as ancient poetry and ancient style. Classical poetry is free in meter, without antithesis, even in level, wide in rhyme and unlimited in length. There are four words, five words, six words, seven words and miscellaneous sentences. Four-character poems no longer exist in modern poetry. Although the word "ancient" is not added, it goes without saying that it is an ancient poem. The ancient poems included in The Book of Songs are mainly four-character poems. Four-character poems were still written in Han Dynasty and Wei and Jin Dynasties. Cao Cao's Looking at the Sea and Tao Yuanming's Stopping Clouds are typical four-character poems. There are many ancient poems with five words and seven words, referred to as five ancient poems and seven ancient poems for short. The ancient Five Dynasties first appeared in the Han Dynasty. Nineteen ancient poems, all five-character poems. After the Han Dynasty, many people wrote five-character poems. Most of the poems in the Southern and Northern Dynasties are five-character poems, and there are more five-character poems in the Tang Dynasty and later. The appearance of the Seven Ancient Dynasties may be earlier than that of the Five Ancient Dynasties. But before the Tang Dynasty, it was not as common as the Five Dynasties. In the Tang Dynasty, seven ancient books appeared in large numbers, which were also called long sentences by the Tang people. Miscellaneous poems are also unique to ancient poetry. Poetry varies in length, from one word to more than one cross. Generally, it is a mixture of three, four, five and seven words, and seven words are the main ones, so it is customarily classified as ancient seven words. There are many miscellaneous poems in The Book of Songs and Han Yuefu folk songs. Since the Han and Wei Dynasties, Yuefu poems have been accompanied by music, including songs, lines, songs and poems. Many Yuefu poems in Tang Dynasty were unhappy. There are various forms of miscellaneous poems in Tang and Song Dynasties: there are seven words mixed with five words, such as Zhang Ji's Difficult to Go; There are seven words mixed with three words, such as Zhang Lei's Cowherd; There are three or five sentences in the seven words, such as Li Bai's "Into the Wine"; There are seven words mixed with two, three, four, five words to more than ten words, such as Du Fu's "The Hut is Blown by Autumn Wind"; There are four, six and eight characters mixed with five or seven characters, such as Li Bai's "Difficult Road to Shu". In addition, ancient quatrains also had authors in the Tang Dynasty. All belong to the category of ancient poetry. In the process of development, classical poetry and modern poetry have an interactive relationship. In the late Northern and Southern Dynasties, a new style of poetry appeared, which emphasized rhythm and duality, but had not yet formed a complete rhythm, and was between classical poetry and modern poetry. Some ancient poems in the Tang Dynasty tend to be legalized, and even ancient works are often integrated into modern sentence patterns. However, there are also some ancient poetry writers who consciously distinguish themselves from the near-body, and often use awkward sentences or occasional essays to avoid the law. Classical poetry is a kind of poetic style as opposed to "modern style". Before the formation of modern poetry, all kinds of poetry genres except Chu Ci were also called ancient poetry and ancient style. This is written according to the practice of ancient poetry, and the form is relatively free, not bound by meter. Informal and straightforward. The rhyme foot is wide, except for the rhyme foot of seven-character white and bright sentences, which generally rhymes with other sentences. The rhyme foot can be flat, flat or variable. There is no limit to the length of space. Sentences can be unified into four-character, five-character, six-character and seven-character fonts, or long and short sentences can be mixed and changed at will, which is miscellaneous. There are many ancient poems with five words and seven words, which are referred to as "five ancient" and "seven ancient" for short. Miscellaneous words range from one word to many crosses, which are generally a mixture of three, four, five and seven words, mainly seven words, so they are customarily classified as seven ancient words. Since the Han and Wei Dynasties, Yuefu poems were originally accompanied by music, including songs, lines, songs and words. The Tang Dynasty imitated the previous Yuefu, such as Li Bai's Difficult Road to Shu, Du Fu's Three Officials, Three Farewells and Bai Juyi's New Yuefu, all of which were out of step and belonged to the category of ancient poetry. In addition, there were quatrains in units of four sentences before the Tang Dynasty, or "archaic quatrains", and there were also writers in the Tang Dynasty, which is different from the recent quatrains, which pay attention to flat and even lines. There is an interactive relationship between ancient poetry and modern poetry in the process of development. In the late Northern and Southern Dynasties, some poems began to emphasize rhythm and duality, but they did not form a complete rhythm. They were a form of transition from ancient poetry to modern poetry, or "new poetry". Some ancient poems in the Tang Dynasty tend to be legalist. For example, Wang Bo's Tengwangge is an ancient poem, but it is flat and harmonious, with eight sentences, which are similar to two seven-character quatrains and two rhymes. After the Tang dynasty's metrical poems were finalized, the poets' ancient works were often integrated into the modern sentence pattern. Such as Wang Wei, Li Qi, Wang Changling and Meng Haoran, there are quite a few rhymes and couplets in the five ancient books. There are also many sentences in Bai Juyi's famous songs such as Song of Eternal Sorrow and Pipa Xing. However, some poets are consciously different from the modern style, often using awkward sentences and occasionally prose, and Li Bai, Du Fu and Han Yu have all created something. Later, scholars in Ming and Qing Dynasties consciously noticed the phenomenon that ancient poems were merged into regular sentences and strange sentences were used to avoid regular sentences. In Qing Dynasty, Wang Shi-Even thought that ancient poems were even numbers, so Zhao Zhixin, Weng Fanggang and others specially studied the tones of ancient poems. Their research has contributed to consciously distinguishing ancient and modern rhythms in poetry creation, but it seems far-fetched and even ridiculed as "invisible and useless" because it ignores the fact that ancient poems are mainly natural syllables.