几何图形千变万化.但是它们大都是由基本图形构成.学好几何的诀窍之一要熟悉基本图形,掌握它的构成,形式及其性质.初中课本中有些例题和习题,蕴涵着极为丰富的内容,就其实用价值而言,它们往往不亚于常用的一些定理.如果在平时的教学和复习中重 Geometry is ever-changing. But most of them are made up of basic graphics. One of the first things to learn about geometry is to become familiar with the basic graphics, grasp its composition, form, and its nature. There are examples and exercises in junior high school textbooks that contain extremely rich content. In terms of their practical value, they are often as good as some of the commonly used theorems. If they are taught and reviewed in peacetime,