{HEAD ~ A voltage stimulus} applied to the drain forces {TAIL ~ current} to flow through the channel coupling the drain to the source 
{ HEAD ~ A voltage stimulus } applied to the drain forces { TAIL ~ current } to flow through the channel coupling the drain to the source
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH