[Problems in Word 2003]

While typing a letter in Word 2003 it changed from English to what looked
like Arabic language. I have rebooted 3 times and started over and still
the same occurs. I even copied what I had in English to an email in Yahoo
and sent it to myself and rebooted. Came back to that same email and copied
it to a new email that I started to myself, and when I started typing it
would only type in what looked like Arabic language.
This happened to me once a couple of weeks ago, but never occurred again
till now.
What do I do?