This handout analyzes the key and difficult knowledge of high school. The language is easy to understand, with a large number of easy-to-understand examples to help you understand. The content setting is scientific and reasonable, the key points and difficulties are prominent, and the context of knowledge is clear, which is convenient for students to master knowledge systematically. The content covers a wide range, including the main knowledge points in compulsory courses, and also adds detailed explanations of hot issues, which is helpful for students to take exams. The overall arrangement is compact and the knowledge framework is complete, which is one of the better teaching materials in the sprint stage of the college entrance examination.