{HEAD ~ Multi head machines} are assembled in {TAIL ~ accordance} with the number of grinding heads on the basis of frame modules which are similar in shape 
{ HEAD ~ Multi head machines } are assembled in { TAIL ~ accordance } with the number of grinding heads on the basis of frame modules which are similar in shape
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH