四则计算是小学数学中最基础的内容之一,对于整数、小数、分数的四则运算,以及它们的混合运算,不仅要计算得正确,而且要做到计算方法合理、灵活。为了达到这个要求,在复习四则运算时,要做到一个“理解”,四个“掌握”。即:理解四则运算的意义;掌握加、减、乘、除法的计算法则,掌握加法与减法、乘法与除法的关系,掌握四则混合运算的顺序,掌握运算定律和性质。另外,要注意两点:一是对于 The four calculations are one of the most basic elements in elementary mathematics. For the four arithmetic operations of integers, decimals and fractions, and their mixed operations, not only are the calculations correct, but also the calculation methods are reasonable and flexible. In order to meet this requirement, when reviewing the four operations, we must achieve an “understanding” and four “mastery.” That is: understand the meaning of the four operations; grasp the rules of addition, subtraction, multiplication and division, grasp the relationship between addition and subtraction, multiplication and division, grasp the order of the four mixed operations, master the law and nature of the operation. In addition, we should pay attention to two points: one is for