A tensioning drive is provided at {HEAD ~ one end} of {TAIL ~ a section} of the predetermined course 
of
A tensioning drive is provided at { HEAD ~ one end } of { TAIL ~ a section } of the predetermined course
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH