Problem med script i RedHat?!

Jag har problem denna kodsnutt ,som har gjort i RedHat
Jag slipper inte ut från while-loopen fast jag trycker skriver
talen mellan 1 och 4. Kan nån hjälpa mig?

clear
while [ "$answer"!1 ] || [ "$answer"!2 ] || [ "$answer"!3 ] || [ "$answer"!4 ]
do
  echo Are you sure you want to log out?
  echo 1. Log out
  echo 2. Shut Down
  echo 3. Restart the computer
  echo 4. Quit
  echo Your answer: 
  read answer
  if [ "$answer">1 ] || [ "$answer"<2 ] 
  then
    echo Please enter 1, 2, 3, 4
  fi
done
if [ "$answer" = 1 ]
then 
  init 3
fi

if [ "$answer" = 2 ]
then 
  shutdown -g0
fi

if [ "$answer" = 3 ]
then 
  reboot
fi

if [ "$answer" = 4 ]
then 
  echo "Nothing happens"
fi[

Är ingen mästare på Shell-script, men finns det inte en del konstigheter?

while [ "$answer"!1 ] || [ "$answer"!2 ] || [ "$answer"!3 ] || [ "$answer"!4 ]

borde vara?

while [ "$answer"!=1 ] || [ "$answer"!=2 ] || [ "$answer"!=3 ] || [ "$answer"!=4 ]

if [ "$answer">1 ] || [ "$answer"<2 ]

borde vara?

if [ "$answer"<1 ] || [ "$answer">4 ]

if [ "$answer" = 1 ]

borde vara?

if [ "$answer" == 1 ]

osv ..