A hybrid vehicle in which an engine can always be driven in {HEAD ~ a highly efficient region} in accordance with {TAIL ~ the required running load} 
A hybrid vehicle in which an engine can always be driven in { HEAD ~ a highly efficient region } in accordance with { TAIL ~ the required running load }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL