《数学教师》1995.3期刊载了题为《一个四边形满足什么条件是平行四边形》的美国《数学教师》选译文章(以下简称“译文”)、“译文”提出了8道平行四边形判定命题,并就其真假逐一作了说明。确如“译文”所言:“所有的说明都适合于中学教师”,并能增进师生“对平行四边形的理解”。特别是译文中构造判定命题的思想方法以及探求反例的教学建议, Mathematical Teachers 1995.3 published an article entitled “A quadrilateral satisfying what conditions are parallelograms” selected by the American “Mathematical Teacher” (hereinafter referred to as “translation”), “translation” and put forward 8 parallelograms to determine the proposition, and Their true and false statements were made one by one. Indeed as the “translation” puts it: “All the instructions are suitable for secondary school teachers”, and can enhance teachers and students “understand the parallelogram”. In particular, the method of constructing the judgment proposition in the translation and the teaching suggestions for seeking counterexamples,