Lithuanian (lietuvių kalba) is the official state language of Lithuania and is recognized as one of the official languages of the European Union. There are about 3.2 million native Lithuanian speakers in Lithuania and about 200,000 abroad. Lithuanian is a Baltic language, closely related to Latvian, although they are not mutually intelligible. It is written in a Latin alphabet. The Lithuanian language is often said to be the most conservative living Indo-European language, retaining many features of Proto-Indo-European now lost in other Indo-European languages. Classification Lithuanian is one of two living Baltic languages, along with Latvian. An earlier Baltic language, Old Prussian, was extinct by the 18th century; the other Western Baltic languages, Curonian and Sudovian, became extinct earlier. Some theories, such as that of Jānis Endzelīns, considered that the Baltic languages form their own distinct branch of the family of Indo-European languages, but the most widely accepted opinion is the one that suggests the union of Baltic and Slavic languages into a distinct sub-family of Balto-Slavic languages amongst the Indo-European family of languages. Such an opinion was first represented by the likes of August Schleicher, and to a certain extent, Antoine Meillet. Endzelīns thought that the similarity between Baltic and Slavic was explicable through language contact while Schleicher, Meillet and others argued for a genetic kinship between the two families. Word order Lithuanian grammar is the study of rules governing the use of the Lithuanian language. Lithuanian grammar retains many archaic features from Proto-Indo European that have been lost in other Indo-European languages, and is consequently very complex. Phonology All Lithuanian consonants except /j/ have two variants: the non-palatalized one represented by the IPA symbols in the chart, and the palatalized one (i.e., /b/ – /bʲ/, /d/ – /dʲ/, /ɡ/ – /ɡʲ/, and so on). The consonants /f/, /x/, /ɣ/ and their palatalized variants are only found in loanwords. Consonants preceding the front vowels /ɪ/, /iː/, /ɛ/, /æː/ and /eː/, as well as any palatalized consonant or /j/ are always moderately palatalized (a feature Lithuanian has in common with the Polish ,Belarusian and Russian languages but which is not present in the more closely related Latvian). Followed by back vowels /äː/, /ɐ/, /oː/, /ɔ/, /uː/, and /ʊ/, consonants can also be palatalized (causing some vowels to shift; see the "Vowels" section); in such cases, the standard orthography inserts the letter i between the vowel and the preceding consonant (which is not pronounced separately), e.g. noriu [ˈnôːrʲʊ]. Most of the non-palatalized and palatalized consonants form minimal pairs (likešuo [ʃuə], "dog – šiuo [ʃʲuə], "with this one"), so they are independent phonemes, rather than allophones.