Solution:

Let's start observing from the first group on the left. The blue rectangle remains unchanged, but the red heart has flipped, with its corner pointing up. The red heart has changed position. Look at the second group, the blue triangle remains unchanged, but the red heart has flipped, with its corner pointing up. Based on this pattern, what should the third group be like? The blue circle should remain unchanged, and the red heart should flip! Therefore, ② is the correct choice for the third group. Follow the same logic for the fourth group. The blue parallelogram should remain unchanged, and the red heart should flip. Therefore, ③ is the correct choice for the fourth group.

Solution:

1. Let's start with the first group on the left. There is a square in the triangle and also a square in the circle. The result is a square. In the middle group, there is a circle in the sunflower shape and also a circle in the quadrilateral. The result is a circle. In the group on the right, there is a star in both shapes. What should the result be? Correct, it should be a star shape.
2. Follow the same pattern and start from the left. A rectangle can be found in both shapes, so the result is a rectangle. In the middle group, a trapezoid can be found in both shapes. So the result is a trapezoid. In the group on the right, what shape can be found in both shapes. It is a heart shape.