{HEAD ~ The pair} of {TAIL ~ flanges} and the pair of webs form a closed sectional part 
{ HEAD ~ The pair } of { TAIL ~ flanges } and the pair of webs form a closed sectional part
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH