The seat, arm rests, foot rest and back rest form {HEAD ~ a chair} for {TAIL ~ the user} 
for
The seat , arm rests , foot rest and back rest form { HEAD ~ a chair } for { TAIL ~ the user }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL