[主持人按本期两篇的共同点是：课题内容虽略显平谈，是并不怎么难于处理的教材．然而，设计人恰在平谈之中显示出了它的不平淡，深思熟虑后发掘出了它的思想方法内涵：丁老师意识到解数学问题也常常是“起头难”，在他的这一节课中，就深谋远虑地引导学生，在“问题的数学化” [The moderator’s common denominator of the two articles in this issue is: Although the content of the project is slightly flat, it is not very difficult to handle. However, the designer showed his bleakness in the conversation. After pondering carefully, he unearthed the connotation of his thoughts and methods. Teacher D was also aware that solving problems in mathematics was often a “difficult start” in his section. In the class, he guided the students in a far-sighted way, “Mathematicalization of the problem.”