Answer:
a kite
Step-by-step explanation:
Yes, you can form a kite. The top two would be 2 units, and the bottom two would be 4 units. It would still have two of each, just like the rectangle, but would be a different quadrilateral.
Alternately, you could turn the rectangle into a parallelogram by leaning it. Rectangles have 90 degree angles, so it wouldn't be a rectangle anymore.