读本刊 2 0 0 2年第二期《椭圆第二定义中来自学生的几个问题及对策》后 ,颇有同感 ;同时笔者也有一个该文未提及 ,而教学中每届都有学生提出且颇引起全班同学共鸣的问题 :如果不是象教材中那样布列等式组复杂变形最后化成标准方程的话 ,从“直观”上实在看不出分别满足椭圆两? After reading the second issue of “Some Questions and Countermeasures from the Students in the Second Definition of the Ellipse” in the second issue of the magazine in 2002, this article is quite the same; at the same time, the author also has one article that is not mentioned in this article, and there are students in each session of the teaching. The question raised and quite aroused the sympathy of the classmates: If it is not the same as the textbook, the complex deformation of the equations will eventually be converted into the standard equation. From the “intuitive” aspect, we cannot see that the ellipse meets the two respectively.