What Is a Circle?
What Is a Triangle?
What Is the Angle Sum of a Triangle?
What Are Acute, Obtuse and Right Triangles?
What Is a Polygon?
What Is a Quadrilateral?
What Is the Angle Sum of a Quadrilateral?
What Are Rectangles, Squares, Parallelograms and Rhombuses?
How do you classify two-dimensional figures into categories based on their properties?