在卫校统编教材《数学》第三版的第三章中，由于排列、组合概念的抽象，解决问题方法的特殊，计算的复杂，学生感到“概念难于理解，解题没有把握”。而这部分知识是发展学生抽象能力和逻辑思维能力的主要题材，也是进一步学习概率论及卫生统计学的基础。教师在讲授这部分内容? In the third chapter of the third edition of the math textbook “Mathematics”, the students felt that “the concept is hard to understand and the problem solving is not certain” due to the abstract arrangement and combination concept, the special solution to the problem and the complicated calculation. This part of knowledge is the main theme of developing students' abilities of abstraction and logical thinking. It is also the basis for further studying probability theory and health statistics. Teachers are teaching this part of the content?