Although English is by far the predominant language in the United States, the United States has no official language. Attempts to make English the official US language have never even come close to succeeding. Spanish is the second most common, by a huge margin. There are many ethnic enclaves in which many languages other than English predominate; for example, Somali in parts of Minneapolis; Chinese in parts of Quincy, Massachusetts (and in the "Chinatowns" of many big cities).

Authorities in some places will provide things like tax forms or voting instructions in the most important local languages. In the Boston public transportations system, notices in the public transit system are in English and Spanish. The local high school in my town provides copies of the student handbook in English, Spanish, Portuguese (probably Brazilian Portuguese but I don't know), Haitian French, and Arabic.

Hi Natasha 

Flemish is the Dutch variant spoken in the Northern region of Belgium, but it has never been part of our official languages. In official terms, we make a distinction by saying 'Dutch-Dutch' and 'Belgian-Dutch'. Flemish is more used to indicate the dialect we speak in Flanders but, then again, every region in Flanders has its own dialect. 

It's a difficult topic as there has been a million discussions to make Flemish another official language in Belgium. In my personal opinion, I prefer to say Dutch is my mother tongue and Flemish is the dialect I speak with friends and family. 

Regards

Karen