“母题”就是指在某一单元或某一章节具有代表性的典型例题,扩编是依从知识的内在联系、逻辑顺序不断地变换“母题”中已知条件或待求物理量,设问引路,逐步纵向深入,横向拓宽,发展问题的内涵和外延,以便覆盖到全章节的知识点,提高解题的能力.本文举例说明. “Motif” refers to a typical example in a unit or a chapter. The expansion is based on the internal connection of the knowledge and the logical sequence to continuously change the known condition or physical quantity to be solved in the “mouse”. Lead the way, gradually deepen horizontally, widen the landscape horizontally, develop the connotation and denotation of the problem, so as to cover the knowledge of the whole chapter and improve the ability to solve problems. This article gives an example.