I use this code to draw three-dimensional and show the curves at the bottom. But does not give me the result required u[x_, y_] := x + y - x y contour = ContourPlot[u[x, y], {x, 0, 1}, {y, 0, 1}, PlotRange -> {0, 1}, Axes -> False, Contours -> 15, PlotPoints -> 50, PlotRangePadding -> 0, ContourShading -> {{Opacity[.3], Blue}, {Opacity[.8], LightBlue}}]; potential1 = Plot3D[u[x, y], {x, 0, 1}, {y, 0, 1}, PlotRange -> {0, 1}, ClippingStyle -> None, MeshFunctions -> {#3 &}, Mesh -> 15, MeshStyle -> Opacity[.5], MeshShading -> {{Opacity[.3], Blue}, {Opacity[.8], LightBlue}}, PlotRange -> {Automatic, Automatic, {min, 2}}, Lighting -> "Neutral"]; Show[potential1, Graphics3D[contour[[1]] /. {x_Real, y_Real} :> {x, y, 0}], BoxRatios -> {1, 1, 0.6}, FaceGrids -> {Back, Left}] > [![enter image description here][1]][1] I need to have a three-dimensional drawing(plot3D) that shows curves only better as in the following pictures(Figures). [![enter image description here][2]][2] [![enter image description here][3]][3] Is there a similar result to this piloting as in the pictures? Or it's in other programs? Thanks for the help. [1]: https://i.sstatic.net/Vc7en.png [2]: https://i.sstatic.net/ZEbbI.png [3]: https://i.sstatic.net/FD3Px.png