Hungarian, Czech and Slovak in Vienna and Burgenland, under the European Charter for Regional or Minority Languages. In the Czech Republic, several municipalities of Zaolzie area have official bilingualism (Czech and Polish). Bilingual signs are permitted if a minority constitutes at least a 10% of the population of the municipality. German is recognized as a minority language because of the previous visible German presence in Bohemia. Germany has German as its official national language. Low German is recognized as a regional language in at least five north German states. Low Rhenish is recognized in North Rhine-Westphalia. Lower Sorbian is an official minority language in Brandenburg, Upper Sorbian in Saxony, Sater Frisian in a part of Lower Saxony, and North Frisian varieties and Danish in Schleswig-Holstein. A language without its own territory, Romany (including the language of the Sinte people) is an official minority language as well. Germany is home to large numbers of people from other regions, and some of their languages, such as Turkish, Russian, and Polish, are widely used throughout the country. However, those languages are considered foreign and thus are given no official status. Hungary, the official language is Hungarian. The country recognizes Beás, Croatian, German, Romani, Romanian, Bosnian, Serbian, Slovak, Slovene languages. Use of those languages for certain functions is provided for by law, applying to localities where the share of a relevant minority exceeds 10% or, for wider functions, 20%. Poland — 20 bilingual communes in Poland (mostly Polish-German) speak forms of the German language. Belarusian, Czech, Hebrew, Yiddish, Lithuanian, German, Armenian, Russian, Slovak, and Ukrainian are recognised as national minorities languages while Karaim, Lemko, Romani, and Tatar as ethnic minorities languages. Slovakia has a Hungarian minority of 520,000 (9.7%). Bulgarian, Croatian, Czech, German, Bosnian, Serbian, Hungarian, Polish, Roma, Russian, Ruthenian, and Ukrainian languages are recognized as regional or minority languages, with guarantees of their use in municipalities where Slovak citizens belonging to the national minorities form at least 20% of the population. Switzerland has four national languages; German, French, Italian, and Romansh. The cantons Valais, Fribourg and Bern are bilingual (French and German), while canton Graubünden is trilingual (German, Romansh, and Italian). Most of the Swiss nowadays find out easily to learn English to communicate to Swiss speaking other native languages, as English is neutral among speakers of different national languages, making it a lingua franca, with no one national language dominating the other.