In practice, there are situations where elements with elliptical form are necessary.
To create a plate that has an elliptical outline or a curved beam that follows an elliptical path you must draw an elliptical polyline.
By default, AutoCAD draws ellipses that are not made of polylines and cannot be used as basis of a plate or a beam. Therefore you must set AutoCAD to draw ellipses as polylines.
Once the value is set, you can create ellipses and modify them to create the shape that you need.
After the editing is finished, the new shapes can be converted into plates or beams using the corresponding command.