Use 4 pieces of the jigsaw puzzle to form an isosceles trapezoid. The specific steps are as follows:
1. First find a small square in the jigsaw puzzle, and based on this, Create an isosceles trapezoid.
2. Place two right triangles on both sides of the square to form a trapezoid.
3. Finally, find a parallelogram in the tangram and place it next to the assembled trapezoid to form a complete parallelogram.