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