{HEAD ~ An exemplary method} involves {TAIL ~ detection} of single molecules of fluorescent labels released from a nucleic acid during synthesis of an oligonucleotide 
involves
{ HEAD ~ An exemplary method } involves { TAIL ~ detection } of single molecules of fluorescent labels released from a nucleic acid during synthesis of an oligonucleotide
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH