Freestyle > Adding Detail to the Control Mesh > Connecting Mesh Elements > To Connect Mesh Elements
  
To Connect Mesh Elements
1. Create or import a shape.
2. Select a pair of faces or edges on the control mesh. Select the first face or the edge and then hold down the CTRL key and select the next one. The dragger appears on the mesh element that you last selected.
3. Right-click the graphics window and click . Alternatively, click Freestyle > Connect. The selected pairs of faces or edges are connected.
 
* Verify whether the orientation of the shapes that you are connecting is as desired. Right-click the shapes in the Feature Tree and select Flip Normal to flip the orientation.