This reduction state is sustained until the desired effects are obtained and {HEAD ~ the temperature} may be held to lengthen {TAIL ~ this reduction} 
held to lengthen
This reduction state is sustained until the desired effects are obtained and { HEAD ~ the temperature } may be held to lengthen { TAIL ~ this reduction }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL