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