有些几何问题看上去很容易解决,但动手做一做却可能走入了“迷宫”.这时候,我们不妨尝试添加辅助线,构造一些特殊的三角形,有可能找到“出路”.由于三角形是一种最基本的几何图形,它的出现往往能使问题中题设和结论的关系明朗化,从而帮助我们顺利解题.下面介绍几种构造三角形解题的方法. Some geometric problems seem to be easy to solve, but it may be possible to go into the “maze” with hands-on. At this time, we may try to add auxiliary lines, construct some special triangles, and possibly find out the way out. Because the triangle is a kind of basic geometric figure, its appearance can often make the relationship between the questions and conclusions in the problem clear, and thus help us to solve the problem smoothly. The following introduces several methods for constructing triangles.