Today, {TAIL ~ the trend} is to increase the temperature of {HEAD ~ operation} of gas turbine engines 
Today , { TAIL ~ the trend } is to increase the temperature of { HEAD ~ operation } of gas turbine engines
OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH