"Typical examples" of almost all chapters have been replaced. This is of great guiding significance for preparing for the exam and keeping about one-third of the mathematics subjects in the annual exam.

For example, in Chapter 6, "Inequalities", simple linear programming problems and large inequality problems are added to typical examples, which strengthens the investigation of basic inequalities and double absolute inequalities. This is worthy of our attention, especially for linear programming problems and double absolute value inequalities.

For example, the fourth polar coordinate is added in Chapter 8 "Equation of Line and Circle", and a lot of questions about polar coordinate and parametric equation are added in typical examples. The polar coordinate part appeared in previous exams, but it has been added in this year's new syllabus and new textbooks. Therefore, it is speculated that the probability of "polar coordinate" appearing in the exam in 2020 is very high, and there is a great chance of getting the original title, especially the1-1in the typical examples and1in the blank space.