set {HEAD ~ one or more soft limits} to define {TAIL ~ a second range} within the first range; and 
to define
set { HEAD ~ one or more soft limits } to define { TAIL ~ a second range } within the first range ; and
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH