平行线和相交线是“空间与图形”所研究的最基本的问题,是我们今后继续学习的基础．由于同学们初学几何,解题时难免会出现这样或者那样的错误．只要深入思考,掌握数学语言表述问题的规律,准确理解概念,就可以逐渐避免错误的发生．本文举例说明解平行线和相交线问题常犯的错误,请同学们引以为戒． Parallel lines and intersecting lines are the most basic issues studied in “Space and Graphics” and are the basis for our continued learning. As the students begin to learn geometry, it will inevitably lead to such or such mistakes. As long as you think deeply, master the laws of mathematical language expressions, and understand concepts accurately, you can gradually avoid mistakes. This article illustrates the common mistakes of solving parallel lines and intersecting lines. Ask the students to take warning.