推广是一个命题经过一般化所得到的正确结论，正如波利亚所说：“是从好的东西中提炼更纯净的精制品”，好的推广是“不容易得到的”，因此，推广不能单纯地看成是一个命题简单的一般化，而应抓住命题成立的本质，否则，很可能推出错误的结论，以如下命题的推广为例．命题如果P Promotion is the correct conclusion that a proposition has been generalized. As Polya said: “It is from the good things to refine pure products.” Good promotion is “not easy to obtain.” Therefore, promotion cannot Simply consider it as a simple generalization of the proposition, but should grasp the essence of the proposition. Otherwise, it is likely to introduce wrong conclusions. Take the promotion of the following proposition as an example. Proposition if P