Please follow this guidelines to translate into Arabic.
For now, I have to revert your changes (the translation is kept on History page). Sorry.
but there are nothing about Arabic or Persian language. can you help me?
What kind of help do you need?
You just need a translator account (the instruction is given by the link above).
Once you've got your account you will see a link to translate the page. On that new page there is a drop-down list of languages. Choose your language there and Fetch the messages. It will be easy once you have seen that. If you apply for the account now I can authorise it before I leave for the night.