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
Seat of the European Parliament in Strasbourg on 1 September was moved to the Brussels hemicycle. Parliament was expected to move back to Strasbourg for the session starting on 22 September but had to remain in Brussels for that session as well as safety inspections dragged on. The event was greeted with joy by those who oppose the Parliament's presence in Strasbourg, and mocked by eurosceptics who wore hard hats to the first plenary in Brussels after the incident (if Parliament had been sitting at the time, the collapsing ceiling would have hit members of the eurosceptic parties). In August 2012, the Paul-Henri Spaak building in Brussels