The Mongolian language (in Mongolian script: ᠮᠣᠩᠭᠣᠯ
ᠬᠡᠯᠡ Moŋɣol kele; in Mongolian Cyrillic: монгол хэл, mongol khel) is the official language of Mongolia and both the most widely-spoken and best-known member of the Mongolic language family. The number of speakers across all its dialects may be 5.2 million, including the vast majority of the residents of Mongolia and many of the Mongolian residents of the Inner Mongolia Autonomous Region. In Mongolia, the Khalkha dialect, written in Cyrillic (and at times in Latin for social networking), is predominant, while in Inner Mongolia, the language is dialectally more diverse and is written in the traditional Mongolian script. In the each other discussion of grammar to follow, the variety of Mongolian treated is Standard Khalkha Mongolian (i.e., the standard written language as formalized in the writing conventions and in the school grammar), but much of what is to be said is also valid for vernacular (spoken) Khalkha and for other Mongolian dialects, especially Chakhar.
Some classify several other Mongolic languages like Buryat and Oirat as dialects of Mongolian, but this classification is not in line with the current international standard.
Mongolian has vowel harmony and a complex syllabic structure for a Mongolic language that allows clusters of up to three consonants syllable-finally. It is a typical agglutinative language that relies on suffix chains in the verbal and nominal domains. While there is a basic word order, subject–object–predicate, ordering among noun phrases is relatively free, so grammatical roles are indicated by a system of about eight grammatical cases. There are five voices. Verbs are marked for voice, aspect, tense, and epistemic modality/evidentiality. In sentence linking, a special role is played by converbs.
Modern Mongolian evolved from Middle Mongol, the language spoken in the Mongol Empire of the 13th and 14th centuries. In the transition, a major shift in the vowel-harmony paradigm occurred, long vowels developed, the case system changed slightly, and the verbal system was restructured. Mongolian is related to the extinct Khitan language. It was believed that Mongolian is related to Turkic, Tungusic, Korean and Japonic languages but this view is now seen as obsolete. These languages have been grouped under the now discredited Altaic language family and contrasted with the Mainland Southeast Asia linguistic area. Mongolian literature is well attested in written form from the 13th century but has earlier Mongolic precursors in the literature of the Khitan and other Xianbei peoples. The Inscription of Hüis Tolgoi dated to 630 CE is currently the oldest substantial Mongolic or Para-Mongolic text discovered.