The cycle is then repeated {TAIL ~ a sufficient number} of times to transfer a sufficient amount of gas from the gas supply line to the on board storage, at {HEAD ~ the necessary pressures} 
The cycle is then repeated { TAIL ~ a sufficient number } of times to transfer a sufficient amount of gas from the gas supply line to the on board storage , at { HEAD ~ the necessary pressures }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD