The control unit controls print of a background design image by the first development unit and print of {HEAD ~ a print image} by {TAIL ~ the second development unit} 
by
The control unit controls print of a background design image by the first development unit and print of { HEAD ~ a print image } by { TAIL ~ the second development unit }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL