Generally speaking, the initial knowledge span is very large. The total amount of knowledge learned in junior high school for three years is not even as good as that learned in senior high school for one year. For example, mathematics, high school mathematics science students need to study ten books, and each book has an important test center for the college entrance examination. The number of English words has increased from 1600 required by junior high school to 3500 words +500 phrases. So at the beginning of the new high school, many students will have the feeling of "hitting the wall", which is also commonly known as the steep slope effect.