2. In calligraphy, the word "make good use of Su Mo" refers to Su Mo, that is, after being poured out overnight, part of the ink has dried up and scabbed, and the ink has thickened, because the dry knot produces dregs, which is both black and layered when used, and the good user can play this feature.
3. Su Mo is one of the seven laws, which refers to the ink in inkstone. The ink is degummed, sticky and thick black, with water next to it, and pen marks still exist. It has its own misty rain flavor, and calligraphers use it to awaken the spirit of the picture and play the role of Su Mo.