Power generator 26 and {HEAD ~ second power generator} 28 may provide equal power or may provide {TAIL ~ different power amounts}  
provide
Power generator 26 and { HEAD ~ second power generator } 28 may provide equal power or may provide { TAIL ~ different power amounts }
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH