The Digitizer editing tools found under the Crop/ Combine/ Split Functions 
 sub-menu allows users to combine, subdivide and cut selected (and overlapping) 
 features. The options available on this menu will vary slightly depending 
 on the features selected.  
 Split Line At Selected Vertex
 Split Line At Selected Vertex Crop to Selected Areas
 Crop to Selected Areas Cut Selected 
 Areas from Another Area (Add Islands)
Cut Selected 
 Areas from Another Area (Add Islands) Combine Line Features
Combine Line Features Combine Selected Area Features
Combine Selected Area Features