{HEAD ~ The base} 12 has {TAIL ~ a top surface} 16 and a bottom surface 18 opposite thereto 
has
{ HEAD ~ The base } 12 has { TAIL ~ a top surface } 16 and a bottom surface 18 opposite thereto
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH