Urdu would be of the most benefit for you. Most of the Muslim people round here (I live in Plaistow) do not understand Arabic, save for reciting the Qu'ran. And pretty much everyone in south Asia can get by with Urdu even if it is not their first language- that is, according to my mates. It's a multipurpose one that. If I was to learn a language for use in the borough I'd pick Urdu, based on my knowledge of 'what language people speak at home.' However I don't know of anyone who's been here ten years and can't speak English, except people born either deaf or with severe learning difficulties of course. I assume you exclude them? -PP