{TAIL ~ An internal combustion engine} is provided having {HEAD ~ a pair} of cylinders interconnected by means of a narrow connecting channel 
{ TAIL ~ An internal combustion engine } is provided having { HEAD ~ a pair } of cylinders interconnected by means of a narrow connecting channel
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH