A frame of {HEAD ~ a pair} of {TAIL ~ glasses} has a pair of eye rims with front surface and nasal regions which are connected together by a bridge with a front surface and a nasal region 
of
A frame of { HEAD ~ a pair } of { TAIL ~ glasses } has a pair of eye rims with front surface and nasal regions which are connected together by a bridge with a front surface and a nasal region
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH