在梯形计算与证明中 ,学生一碰到稍微复杂的问题就束手无策 ,教材和一些资料上有关这方面的介绍往往是隐性形式 ,并且不够系统、全面 .实质上解决这类问题的关键是如何添加辅助线 ,将问题转化到三角形或平行四边形中去讨论 .下面介绍几种转化方法和技巧 ,供同行参考 .1　作梯形 In trapezoidal calculations and proofs, students are at a loss when they encounter a slightly more complicated problem. The introduction of teaching materials and some materials in this regard is often an implicit form, and it is not systematic and comprehensive. The key to solving such problems is essentially how Add an auxiliary line to convert the problem into a triangle or a parallelogram for discussion. Here are some conversion methods and techniques for reference by peers. 1 Trapezoidal