Flash MX doesnt have a spell checker- you will have to use an external program (text edit or similar) Didnt you write it out first? If you did, just copy the text back in, or link to the external txt file- this is much better, and easier to update.
add to the text file something like
&frame1text=what ever you want to appear on frame one&frame2text=what ever you want to appear on frame two&
(the '&' symbol is what tell Flash a new variable is being declared in an external text file)
Then in your movie, to pull in external text, use
loadVariablesNum("textfile.txt",0)
(it must be a plain text file, not rich text)
change the text box on the stage to a dynamic text box, (in the properties bar) and make it multi-line, and give it a variable name ie 'mytextbox'
on the frames where the text changes, use
mytextbox=frame01text
or what ever the correct var in the text field is called.
You could be really clever, and just set up one function for the lot, say if a button is what progresses to the new sections, something like:
on(press){
mytextbox=this["frame"+_currentframe+"text"]
}
but i dont know how much you know- if you want more help, post back
Chris