Paraguayan Guarani, or simply Guarani (avañe'ẽ), is a language of South America that belongs to the Tupi–Guarani branch of the Tupian language family. It is one of the two official languages of Paraguay (along with Spanish), where it is spoken by the majority of the population, and where half of the rural population are monolingual speakers of the language. Variants of the language are spoken by communities in neighboring countries including parts of northeastern Argentina, southeastern Bolivia and southwestern Brazil. It is a second official language of the Argentine province of Corrientes since 2004 and the Brazilian city of Tacuru since 2010. Guarani is also one of the three official languages of Mercosur, alongside Spanish and Portuguese. Guarani is one of the most widely spoken Native American languages and remains commonly used among the Paraguayan people and neighboring communities. This is unique among American languages; language shift towards European colonial languages (in this case, the other official language of Spanish) has otherwise been a nearly universal phenomenon in the Western Hemisphere, but Paraguayans have maintained their traditional language while also adopting Spanish. The name "Guarani" is generally used for the official language of Paraguay. However, this is part of a dialect chain, most of whose components are also often called Guarani.