Changing text color for certain words only ?

Ok, Im developing a scripting tool for the program "FPS Creator". The scripting uses of course commands which are split into to groups (Action and Condition)

Anyway to the point :

I need the Actions and Conditions to be coloured so the user knows when the command is correct or incorrect.

Is there anyway I can do this ?

Thanks :)

EDIT :

I forgot to say, Im using a richtextbox

Try searching the board for "syntax highlighting" - its been covered quite a lot!

Thank you :D