This forces the container downwardly against {HEAD ~ a forming surface} having {TAIL ~ a configuration} corresponding to a desired configuration of the pieces of material 
This forces the container downwardly against { HEAD ~ a forming surface } having { TAIL ~ a configuration } corresponding to a desired configuration of the pieces of material
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH