The foremost edge of the hydrofoil comprises {HEAD ~ a slot} covered by a continuously adjustable gate for controlling {TAIL ~ the overall drag} imposed by the turbine 
The foremost edge of the hydrofoil comprises { HEAD ~ a slot } covered by a continuously adjustable gate for controlling { TAIL ~ the overall drag } imposed by the turbine
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH