The four tones of Putonghua are: flat tone (the first tone), flat tone (the second tone), rising tone (the third tone) and falling tone (the fourth tone).
For example:
BRIC
(flat tone) (rising tone) (rising tone) (falling tone)
To put it simply, among the four tones of Putonghua, the first and second tones are flat tones; The third and fourth sounds are ligatures.
Extended data
The purpose of leveling:
The artistic conception of poetry can give people a sense of beauty, please readers, or convey feelings and inspire people. So some people think why not let the voice of poetry also give people a sense of beauty, so that it can be read in a cadence, catchy and flat.
With the deliberate development of the leveling theory, to a certain extent, it later restricted the exertion and expansion of the poetic momentum and artistic conception, and became the lame shoes or burdens of the poet, which greatly went astray and violated his original intention. Therefore, whether creating or judging the quality of poetry, modern people should not stick to the theory of poetic rhythm and level, but should focus on the artistic conception and momentum of poetry. As for the tone of poetry, it can be smooth.
References:
Baidu Encyclopedia-Pingze