It is not easy to master the level tone. As far as modern Chinese is concerned, the first sound and the second sound are flat and rising, and the rising and falling tones are flat. The entering tone characters in ancient Chinese have all been transferred to the "1234" sound in modern Chinese. Therefore, there is no entering tone in modern Chinese, and it is no problem to turn the words of the upper and lower tones, because the three sounds of up, go and enter are ambiguous. However, it is more troublesome to transfer the Rusheng words to Yin Ping and Yang Ping's words. For example, in modern Chinese, "Yi, Chi and Ya" are all flat tones, but in ancient Chinese they are all Rusheng characters. It will be difficult for those who learn to write metrical poems if they recite the entering tone characters of ancient Chinese. However, it is easier to distinguish the flat tones with local dialects, because the pronunciations of Rusheng characters in ancient Chinese are still preserved in southern, Wu, Fujian, Guangdong, Jiangxi, Hunan, Hubei and Sichuan dialects. There are also Shanxi and Inner Mongolia in the north, and the pronunciation of Rusheng characters is also preserved in dialects. Therefore, according to the pronunciation of dialects, it is easier to distinguish flat tones with a formula, that is, to read the five tones of "Yin, Yang, Shang, Qu and Ru" with the words "Bing, Ping, Sick, C and He", such as table.
It can be seen that the word "and" is flat, and the word "flat" happens to be flat, and so on.