The official language of Dubai is Arabic. English is the most spoken language in Dubai. 70% of its population are expatriates who speaks Hindi, Urdu, Bengali, Tagalog, Persian, Chinese, Malayalam and many more.
If you visit government offices and institutions, they would usually speak Arabic most especially if they’ve seen you are an Arab also, but otherwise everybody speaks English fine. In malls, restaurants, hotels, entertainment establishments, English is the primary language they use.