按照乘法是“同数连加的简便运算”这一定义,0×n(n是自然数)的意义容易理解,也不难得出0×n=0的结果;但n×0的意义则不好理解,也不能得出“n×0=0”的结论。n×0也不能利用乘法交换律转为0×n。因为运算定律应建立在运算定义之上,而不能用运算定律来说明运算定义。有一种观点认为,“n×0=0”是一个规定,没有 The meaning of 0 × n (n is a natural number) is easy to understand and it is not hard to come to a result of 0 × n = 0 according to the definition that multiplication is a simple operation with the same number plus. However, the meaning of n × 0 is not well understood , Nor can we conclude that “n × 0 = 0”. n × 0 can not be converted to 0 × n using the multiplication swap law. Because the law of operation should be based on the definition of the operation, and the definition of the operation can not be used to define the operation. There is a view that “n × 0 = 0” is a rule, no