What are the twists and turns in life?

Wave: refers to the "Si" in calligraphy; Folding: refers to turning the pen tip when writing. The original refers to twists and turns in writing. Now compare the ups and downs of the article structure. It is a metaphor that things go through twists and turns and are not smooth (it is also a metaphor that there are many unexpected changes in the process of things). In Wang Jinxi's "Mrs. Wei's brushwork": "Every time you make a wave, you often fold three strokes." "Xuanhe Pu Shu's Internal Nerve of the Emperor" Volume 5: "However, its twists and turns are also meticulous." Calligraphy twists and turns. When using a pen, it is called "wave", which means that each pen has to change its nib three times. After thirty percent off, the strokes are vigorous. Feng Fang's "Ji Shu" in the Ming Dynasty reads: "Yi Song, a disciple of Zhong You, often folds his pen three times for each wave." In other words, according to records, Yi Song often made the mistake of dragging his feet when he first wrote The Waves. Only under the guidance of Zhong You, can we get the correct way to use the pen. Huang Tingjian's calligraphy in his later years in the Northern Song Dynasty has obvious twists and turns. When writing a painting, the pen should be tied tightly, the neck should be lifted, and the feet should be fully opened, so there are three turns in one stroke; Later, it generally refers to the ups and downs of strokes when writing stippling, which contains euphemism.