贵刊1992年第1期刊登了唐玉坤同志的文章《分式函数y=(ax+b)/(cx+d)(c≠0,a,b不同时为零)的几个性质》(下称[1]文),把高中教材上的这类习题上升到理论高度,读后很受启发。同时,我又认为[1]文中的部分性质值得商榷。即[1] In your first issue of 1992, published in the 1st issue of Comrade Tang Yukun’s article, several properties of fractional function y=(ax+b)/(cx+d) (c≠0, a, b are not simultaneously zero)” ( The article [1] raised the level of exercise in high school textbooks to a theoretical level and was very inspired after reading. At the same time, I also believe that some of the features of [1] are worth discussing. That is [1]