How to write vertical lines in lowercase letters

You must have seen Ling Feijing. According to Tian (one question a day, one word a day), the level of classics requires the author's skill for 30 years. However, the Ling Fei Meridian does not run vertically. Lowercase letters are allowed to run vertically, but not necessarily horizontally. But the upper and lower ends must be on the same line. Like Zhao Mengfu's Tao Te Ching and Pu Ru's Heart Sutra. Wen Zhiming's lowercase letters are vertical, but they are marked. Tian also quoted another calligrapher as saying that it was 10 year, 10 year and 10 year. ? Maybe Master Tian exaggerated a little. But there is really no "shortcut", no tenacious perseverance, and no one can do it without hard work! ? Personally, I think the small characters in the brush strokes are the most difficult to write, and his brushwork and the arrangement of characters are completely different from those in the "big characters". According to Master Tian, when you start writing, there are more empty pens. Structurally, big characters should be "tight" rather than "loose", and small characters should be "loose" rather than "knotted". Everyone is calligraphy, and the lower case is very good!