{HEAD ~ A control part} inspects {TAIL ~ the switch} to produce a condition signal representative of one of the conditions to which the switch is switched 
{ HEAD ~ A control part } inspects { TAIL ~ the switch } to produce a condition signal representative of one of the conditions to which the switch is switched
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH