The workpiece may be a single piece of material or {HEAD ~ a plurality} of {TAIL ~ pieces} of material which are bonded together under the influence of heat and pressure 
The workpiece may be a single piece of material or { HEAD ~ a plurality } of { TAIL ~ pieces } of material which are bonded together under the influence of heat and pressure
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH