{HEAD ~ A chemical reducing agent} may be used to reduce {TAIL ~ the GO} to “reduced graphene oxide” sheets 
used to reduce
{ HEAD ~ A chemical reducing agent } may be used to reduce { TAIL ~ the GO } to “ reduced graphene oxide ” sheets
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH