Thereby, {HEAD ~ the paint} remaining in {TAIL ~ the paint line} is pushed back into the paint supply container 
Thereby , { HEAD ~ the paint } remaining in { TAIL ~ the paint line } is pushed back into the paint supply container
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH