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