The set of {TAIL ~ wheels} is arranged substantially on {HEAD ~ a line} extending through the arbor 
The set of { TAIL ~ wheels } is arranged substantially on { HEAD ~ a line } extending through the arbor
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH