{HEAD ~ The voltage} at the function of D1 and Q1 is {TAIL ~ a square wave} 
is
{ HEAD ~ The voltage } at the function of D1 and Q1 is { TAIL ~ a square wave }
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL