A quick round tour
To know only one language is abnormal. At least this is what the statistics say. The majority of people on this globe can call themselves speakers of at least two languages even if their mastery of each language is not identical. Pure monolingualism is a result either of physical isolation from speakers of other languages or it is the result of cultural isolation. The latter type means that, in an area where more than one language is spoken, the dominant group of language speakers insists that its mother tongue is the standard way of communicating. For them, mastering any other language spoken in the area in question is thus rendered unnecessary.