2. A rectangle with diagonal lines perpendicular to each other is a square, and a square is a special rectangle.

3: A quadrilateral with four equal sides and a right angle is a square.

4. A set of rectangles with equal adjacent sides is a square.

5. A set of parallelograms with equal adjacent sides and a right angle is a square.

6: Quadrilateral with four equal sides and perpendicular diagonals.

1: A quadrilateral with four equilateral sides is a diamond.

2. The quadrilateral whose diagonals are perpendicular to each other and split in two is a diamond.

3. Parallelograms with diagonal lines perpendicular to each other are rhombic.

4. A set of parallelograms with equal adjacent sides is a diamond.

1. A quadrilateral with three right angles is a rectangle.

2. A parallelogram with right angles is a rectangle.

3. A quadrilateral whose diagonal is bisected and equal is a rectangle.

1: Two groups of parallelograms with parallel opposite sides are parallelograms.

2. A set of parallelograms with parallel and equal opposite sides.

3. Two groups of quadrilaterals with equal opposite sides are parallelograms.

4. Two groups of quadrangles with equal diagonals are parallelograms.

5. Quadrilaterals whose diagonals bisect each other are parallelograms.

6. A quadrilateral with complementary adjacent angles is a parallelogram.