Then, {HEAD ~ a predetermined step} of {TAIL ~ copying} is carried out in the electrostatic copying machine 4 
of
Then , { HEAD ~ a predetermined step } of { TAIL ~ copying } is carried out in the electrostatic copying machine 4
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH