What situations have you encountered that are limited by language and can only be understood but cannot be expressed in words?

The literal interpretation of this sentence is: I can only understand it in my heart, but I can't say it out loud, or it is difficult to have a fixed vocabulary to clearly express such intentions and views. Such descriptions are often used in characters' inner psychological activities and body language, but are rarely used in a certain academic field. Basically, it can be said completely that in any academic field, there is no such thing as the so-called "can only understand but cannot express". This kind of statement that puts a mysterious veil on calligraphy for no reason is either deliberately deceiving or pretending to be profound. It is entirely out of personal ulterior motives and does not come from the art itself. Learning calligraphy certainly requires a smart mind, but it also requires long-term, fast writing skills and diligent study and practice. Whether it is the extremely high-end Zhong, Zhang, Xi, Xian in history, or the modern hard pen that is closest to the common people, they are inseparable from the original intention of love, and they are also inseparable from diligent study and study. Every time there is a succession of teachers, it is a tireless teacher who teaches, teaches, and solves doubts, transforms people's minds, enlightens human nature, creates the foundation of creation, and ultimately achieves the ultimate pursuit of academic goals. If a teacher fails to explain the important points every time, we can only say that the teacher is incompetent and unqualified, and there is no other explanation.