How to explain the peace in ancient poetry

Chinese pronunciation has tones, such as four tones in Mandarin. The ancients also had four tones, different from Mandarin, which were divided into flat, upper, lower and inner tones. Through long-term practice, the ancients found that different tones combined into sentences sounded like music, and the cadence was very pleasant to hear, so they stipulated that the sentences of poetry should be written according to the correct tone combination, which is the origin of the so-called leveling.

The "ping" in ancient poetry is the flat sound; Everybody else up, down, in. Modern poems, such as quatrains and quatrains, have no more requirements for pouting, just pouting. Take Li Bai's "Early Sending Baidicheng" as an example, which belongs to the seven-line format of the first sentence rhyme. Leveling and leveling requirements are as follows:

Flat (rhyming)

At dawn, I left the White King City which stood in colorful clouds.

Flat Tiles Flat Tiles (rhymes)

Down the river again, a thousand miles a day to Jiangling.

Very flat, very flat.

The screams of monkeys on both sides of the strait

Flat (rhyming)

When my boat left behind ten thousand mountains.

Some of these words have different pronunciations in ancient and modern times, such as "Bai", which belongs to Putonghua and is considered as "Ping", and the ancient pronunciation is similar to "Bo", which is a measure.