对于有些几何题的图形而言,如果我们的目光仅仅囿于原几何图形,往往要经过曲折艰辛的探索,才能找到通幽的小径,甚至会见到“此路不通”的告示牌。如果我们巧妙地“补缺为全”,还其本来的“面目”,根据某些特殊图形的性质,就能发现解题的捷径,顿时有柳暗花明之感。今以中考或竞赛题为例介绍几种常见的“补缺为全”的类型,供同学们参考。 For some geometric figures, if we look beyond the original geometry, we must go through arduous and arduous explorations to find the trails that lead to them, and we may even see a sign saying “This road is not accessible”. If we subtly “fill the gaps for the whole” and return the original “face”, according to the nature of certain special graphics, we can find shortcuts to solve problems, and suddenly there is a sense of desolateness. In this paper, we will introduce some common types of “filling in for the whole” to the students for reference.