Geometry is taught to establish a solid foundation in mathematics and spatial reasoning, promoting a comprehensive understanding of shapes, spatial relationships, and mathematical concepts. This set of the Study of Lines 3-Part Cards includes 15 concepts: curved line, straight line, ray, line segment, origin, endpoints, horizontal line, vertical line, oblique line, parallel lines, divergent lines, convergent lines, intersecting lines, perpendicular lines, transversal line. To use 3-part cards,