[5][6] Variants of the language are spoken by communities in neighboring countries including parts of northeastern Argentina, southeastern Bolivia and southwestern Brazil.

[10] Guarani is one of the most widely spoken Native American languages and remains commonly used among the Paraguayan people and neighboring communities.

[citation needed] Modern scholarship has shown that Guarani was always the primary language of colonial Paraguay, both inside and outside the reductions.

Following the expulsion of the Jesuits in the 18th century, the residents of the reductions gradually migrated north and west towards Asunción, a demographic shift that brought about a decidedly one-sided shift away from the Jesuit dialect that the missionaries had curated in the southern and eastern territories of the colony.

[12][13] By and large, the Guarani of the Jesuits shied away from direct phonological loans from Spanish.

Instead, the missionaries relied on the agglutinative nature of the language to formulate new precise translations or calque terms from Guarani morphemes.

This process often led the Jesuits to employ complicated, highly synthetic terms to convey European concepts.

However, populists often used pride in the language to excite nationalistic fervor and promote a narrative of social unity.

[18] Upon the advent of Paraguayan democracy in 1992, Guarani was established in the new constitution as a language equal to Spanish.

Code-switching between the two languages takes place on a spectrum in which more Spanish is used for official and business-related matters, and more Guarani is used in art and in everyday life.

The letter G̃/g̃, which is unique to this language, was introduced into the orthography relatively recently during the mid-20th century and there is disagreement over its use.

It is not a precomposed character in Unicode, which can cause typographic inconveniences – such as needing to press "delete" twice in some setups – or imperfect rendering when using computers and fonts that do not properly support the complex layout feature of glyph composition.

If an oral vowel is stressed, and it is not the final syllable, it is marked with an acute accent: á, é, í, ó, ú, ý.

Oral /ᵈj/ is often pronounced [dʒ], [ɟ], [ʒ], [j], depending on the dialect, but the nasal allophone is always [ɲ].

The glottal stop, called puso in Guarani, is only written between vowels, but occurs phonetically before vowel-initial words.

This suggests that irregularity in verb forms derives from regular sound change processes in the history of Guarani.

There also seems to be some degree of variation between how much the glottal stop is dropped (for example aruʼuka > aruuka > aruka for "I bring").

[22] /a/, /e/, /i/, /o/, /u/ correspond more or less to the Spanish and IPA equivalents, although sometimes the open-mid allophones [ɛ], [ɔ] are used more frequently.

Reflexive pronoun: je: ahecha ("I look"), ajehecha ("I look at myself") Guarani stems can be divided into a number of conjugation classes, which are called areal (with the subclass aireal) and chendal.

The verb form without suffixes at all is a present somewhat aorist: Upe ára resẽ reho mombyry, "that day you got out and you went far".

Examples are seen below:[30] English has adopted a small number of words from Guarani (or perhaps the related Tupi) via Portuguese, mostly the names of animals or plants.

Other words are: "agouti" from akuti, "tapir" from tapira, "coati" from kuatĩ, "açaí" from ĩwasaʼi ("[fruit that] cries or expels water"), "warrah" from aguará meaning "fox", and "margay" from mbarakaja'y meaning "small cat".

Article 1 of the Universal Declaration of Human Rights in Guarani: Article 1 of the Universal Declaration of Human Rights in English: The New Testament was translated from Greek into Guarani by John William Lindsay (1875–1946), who was a Scottish medical missionary based in Belén, Paraguay.

[39] In 2019, Jehovah's Witnesses released the New World Translation of the Holy Scriptures in Guarani,[40][41] both in print and online.