{HEAD ~ The front wheel} is {TAIL ~ a caster wheel} pivotally attached to an arm directly or indirectly connected to the wheelchair frame 
is
{ HEAD ~ The front wheel } is { TAIL ~ a caster wheel } pivotally attached to an arm directly or indirectly connected to the wheelchair frame
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH