First of all, the lines should have texture, the writing process should be slow and astringent, and it should also reflect flying, so how can the astringency in the later period be produced? In other words, the force applied to the pen should be balanced with the friction. It is necessary to increase the friction when writing to realize the delay of writing. Of course, the intensity of writing should also be increased. You're talking about increasing friction, which means gaining momentum! With the process of writing, the friction gradually disappears until it leaves the paper. Sometimes, the pen has been separated from the paper, but the power of writing has not disappeared. At this time, there will be embellishment or balance painting in calligraphy, or change the order of strokes.
Don't blame yourself for not saying anything.