{HEAD ~ A display control unit} controls {TAIL ~ display} of the data processed by data processing unit on a display terminal 
controls
{ HEAD ~ A display control unit } controls { TAIL ~ display } of the data processed by data processing unit on a display terminal
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH