There are some parts that cause misunderstandings due to incorrect or ambiguous explanations. I felt this myself and the community confirmed it. Especially in the test interpretation section where English is used excessively, detailed explanations of what this means and how to do it are needed for lectures that do not require prior knowledge, so I bought the lecture and listened to it, but it felt like I was quickly reading and reciting content that I already knew. The lecture time is short, so the explanations are light. It seems expensive compared to the content.