Through the Modify menu you can combine different models to generate more complex forms. To do this go to "Modify and Combine." A menu will appear on the screen and you will be prompted to select a Target body and Tool body as well as the type of operation. You can choose between Join, Cut, or Intersect. Once you have your Target and Tool bodies selected hit OK to complete the operation.
*Combine Tool is shown in this example. The blue is the Target body and the red is the Tool body. The operation being preformed is Cut.