The easiest way to display and select a NURBS
component is to press 
on the
object, choose the component type from the marking menu that appears.
With the selection type set, you can then select the component on
the object.
Like curves, NURBS surfaces have CVs that control the shape of the surface. Each patch has a certain number of CVs, controlled by the degree of the curve. To increase the number of CVs you can insert extra isoparms or increase the degree of the surface.
Isoparametric curves (or isoparms) are lines running along the surface in the U and V directions, showing the shape of the surface as defined by the CVs.
