It was really a shame. To be honest with you, that was my biggest issue with the movie, the English speaking aliens. Same as with Thor, and all these other movies. The vampires in Blade have their own language, but aliens from who knows where speak English? It seems arrogant. I know the whole movie magic thing obviously and have heard all possible explanations for it, like "oh maybe they learned it, blah blah blah". We all know why they decided to do it in English and I didn't like that at all. If it were just a popularity thing, then they should have spoken Mandarin. If they didn't worry about aliens speaking it in the actual movie, then just leave the languages alone at this point.
Zod and the rest of his followers could speak all languages on Earth. They're message was broadcast to every electronic device in every language.. So they obviously learnt it when they first arrived in Earth's orbit