{HEAD ~ The training apparatus} 1 wherein {TAIL ~ each} of said at least one transceiver is an ultrasonic transceiver and each of said at least one reflector is an ultrasonic reflector 
wherein
{ HEAD ~ The training apparatus } 1 wherein { TAIL ~ each } of said at least one transceiver is an ultrasonic transceiver and each of said at least one reflector is an ultrasonic reflector
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL 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 OTH