分清谁大谁小，掌握较大数的组成特征昆明市官渡区教研室明启文相差数量关系的三种应用题，尤其是反叙的应用题，是低年级教学的难点。突破这一难点的关憧是：在相比中分清谁大谁小，突出较大数的组成特征。教学第二册中两个数的比较时，耍指导学生分两行各摆出１０个ｔｈ... To distinguish who is young and master the composition of the larger number of Kunming Guandu District Ming-wen, the quantity of the relationship between the three kinds of application problems, especially the application of anti-narrative, is the difficulty of teaching the lower grades. The key to breaking through this difficult point is to distinguish who is young from the other and highlight the compositional features of larger numbers. Teaching the second book when comparing the two numbers, to guide students in two lines each put 10 th ...