I'm leaving a mid-course review. For parts I don't understand, I listen two or three times and absorb them. As a non-major, I had vague fears, but you explain things quite lightly, so mental management is good too. But... the course materials are really too unkind. It might be an occupational hazard, but I feel the frustration of writing proposals with developers. I'm printing them out to read, but there's no basic lecture number matching, and many parts of the class content are missing. It's also inconvenient to view course materials as lectures when there are no lectures. It would be nice if everything could be viewed as PDFs. It's also disappointing when there are lectures but no course materials. It's an affordable and really good lecture, but the course materials are too disappointing. I think it's understandable to receive them separately, but unorganized course materials are really not easy. The lectures are good. It seems like you're trying to make improvements, so I'm leaving a review before completing the course.