Additionally, {HEAD ~ the copolymers} may additionally include {TAIL ~ an initiating constituent} to initiate polymerization 
additionally include
Additionally , { HEAD ~ the copolymers } may additionally include { TAIL ~ an initiating constituent } to initiate polymerization
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH