A second receiving unit of the plurality of receiving units forms {HEAD ~ a selection} for {TAIL ~ the content} and communicating the selection to the first receiving unit 
for
A second receiving unit of the plurality of receiving units forms { HEAD ~ a selection } for { TAIL ~ the content } and communicating the selection to the first receiving unit
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH