#!/bin/bash
### blankline.sh ###

if ...
then
	echo "Usage : $0  ..." ...
         ...   
fi

EOP=false # End Of Paragraph
....
do
   if $EOP 
   then
       echo ;   # add a empty line at the end of previous paragraph
       EOP=...
   fi
   echo "$line"   # Output the line
   [[  .... ]] && EOP=true # End of paragraph reached
.
.
.