China's classical poets attach great importance to the tempering of words, and have the saying of "poetic eye" and "poetic eye". "Eye of Poetry" can be found in Wei Qingzhi's Poet Jade Chips, and "Eye of Poetry" can be found in Lu Shao's Ci Zhi. Generally speaking, it refers to the third word in five words, the fifth word in seven words, and some regard the second word, the fourth word and even the last word as "eyes". In fact, "eyes" are the focus of poetry, regardless of waist, knees and feet.
Specifically, in the key point of poetry, a wonderful word can be vivid, extremely nuanced, difficult to reach, and even create an artistic conception.