The steps and {HEAD ~ processes} that are common to {TAIL ~ many embodiments} of the invention are described below 
are common to
The steps and { HEAD ~ processes } that are common to { TAIL ~ many embodiments } of the invention are described below
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH