Languages of the European Union which is understood by 51% of all adults, while German is the most widely used mother tongue, spoken by 18%. All 24 official languages of the EU are accepted as working languages, but in practice only two – English and French – are in wide general use and of these English is the more commonly used. French is an official language in all three of the cities that are political centres of the Union: Brussels (Belgium), Strasbourg (France) and Luxembourg City (Luxembourg). , the official languages of the European Union, as stipulated in the latest amendment of "Regulation No 1
Institutional seats of the European Union institutions: The European Parliament has its seat in Strasbourg, hosting twelve monthly plenary sessions (including budget session). Brussels hosts additional sessions and committees (including being used in September 2008 for normal sittings when the Strasbourg chamber was damaged). Luxembourg City hosts the Secretariat of the European Parliament. The Council of the European Union has its seat in Brussels, except during April, June, and October, when meetings are held in Luxembourg. The European Commission also has its seat in Brussels, although some departments are hosted by Luxembourg City. The European Court of Justice, the General Court, and the Court of Auditors