how to make a surface from multiple curves in Grasshopper?

please check the rhino file or the JPEG screen shot below.

those are curves I got, and I want to make them into a surface.

even though I tried the Patch command in Rhino, I still have no idea of how to do it in Grasshopper, each time I need to see the variations of the surface, I have to change every single curve manually in Rhino.

Could anybody tell me how to make the variations of that surface by grasshopper?