The lecture content itself was substantial and helpful. However, there was some discomfort in listening to the lecture. During the explanation, the pitch of the voice kept changing, and the rising intonation and expressions like "↗~doing it→" or "What!?" in the speech pattern were repeated, making it difficult to concentrate. Also, in the drawing explanation part, because it was drawn extemporaneously, the shapes were not standardized, and the handwriting was difficult to read, so the image or concept the instructor intended to convey did not come across clearly. Since the content is good, if the delivery method were a little more refined, it would be a much better lecture.