PREUN

/bin/sh

if [[ "$1" = "0" ]]; then
  perl -ni -e "/^THES\s*bg\s*BG\s*th_bg_BG$/ or print" /usr/share/dict/ooo/dictionary.lst
fi

POSTIN

/bin/sh

if [[ ! -f "/usr/share/dict/ooo/dictionary.lst" ]] ||       ! grep -q "^THES[ \t]*bg[ \t]*BG[ \t]*th_bg_BG" /usr/share/dict/ooo/dictionary.lst
then
  echo "THES bg BG th_bg_BG" >> /usr/share/dict/ooo/dictionary.lst
fi