I once witnessed a bunch of fresh recruits tonelessly mumbling through the 'Voila du boudin' as best as they could. It was awesome.
Either way, what I find fascinating is that ISIS must be way more complex and sophisticated than is typically portrayed in media. The image that I have is that of barbarians - but in reality, they must have established some level of civil administration - a jihadist bureaucracy. Would love to learn more about this, in case any journalist is reading this.
[1] http://www.cracked.com/blog/isis-wants-us-to-invade-7-facts-...
ISIS is primarily made up of ex Saddam Hussein henchmen who know a lot about running a state.
2. I doubt they'd "downsize" just because some of their recruits don't speak Arabic well. They need and want all the bodies they can get. I'm sure there's enough overlap in language skills for effective communication.
3. They want to present the image of a civil government, but really it's a jihadist bureaucracy based on what most would consider barbarism.