The intent of this tool is to help Persian speakers type in Persian,
so it does require knowledge of the language. Google has a separate
product, called Google Translate, to do automated machine translation
between languages.
Try out automated English-Persian translation at:
http://translate.google.com/translate_t?sl=en&tl=fa
Of course, since it's a machine-generated translation, it will likely
not be as good as a human translator.