[Koha-translate] Ways to test our translation, and pref po files

Hi What is the best ways to Test what we translate to Arabic. and if we can change and edit translation live on koha and then export po file from koha ? or we have always translate in Pootle then export , then install translation some words we can not give it the right meaning if we do not know its Context in the system . and I want to ask about pref.po file how to add this file to koha After installation I found this link but it is not explain about pref po files : http://wiki.koha-community.org/wiki/Installation_of_additional_languages_for... wish you help me :) thanks a lot . Karam