Series Content LESSON 1 四邊形家族 | Family of Quadrilaterals LESSON 2 平行四邊形特性 | Properties of Parallelograms LESSON 3 辨認平行四邊形 | Identify Parallelograms LESSON 4 菱形/長方形/正方形的特性 | Properties of Rhombuses, Rectangles and Squares LESSON 5 有關特殊四邊形的例題 | Illustrative Examples of Properties of Special Quadrilaterals LESSON 6 中點定理 | Mid-point Theorem LESSON 7 截線定理 | Intercept Theorem