The pronunciation of the word "Jian" can be inferred from the meter of poetry. The level of the first two sentences is:
Guazhou Yishuijian and Jingkou (mediocre)
Zhongshan is only separated by several mountains (flat and flat)
Flat tone and rising tone are flat tone, rising tone and falling tone are boring tone. There was your life in ancient times, and your life belongs to your life. "One" and "Ge" were intoned in ancient times.
From the perspective of metrical requirements, the first sentence is an oblique rise and fall, and the standard format is "oblique fall and oblique fall", so the word "between" must be flat and cannot be pronounced (oblique). The word "Jing" is flat. Even if it doesn't conform to the rules, it belongs to "135 regardless".