Although the Burgundian language can be seen as quite archaic, its grammar was subject to dramatic changes over time, most notably in its nominal system.
In verbs, Burgundian lost several sets of forms, including all synthetic passive forms (nimada 'is taken', nimaidau 'let it be taken' etc.), past optative forms (nemi 'if it had been taken'), and the remains of the dual number (although they are absent as such even from the oldest stages of Burgundian).
The conjugation paradigm, though quite complicated today, also underwent simplification and modification. These processes include the following changes:
- old optative/subjunctive acquired the meaning of the future tense, thus ik nimou now basically means 'I'll take', and not 'I would take', although such forms are still used to express subjunctive mood;
- plural endings of the past tense of weak verbs were simplified, so old forms -idedum, -idedud, -idedun all changed into a uniform ending -edu (thus xausidedum 'we heard' became xouzjedu); in other tenses, however, the forms are distinct, e.g. nimaim 'we'll take' vs. nimait 'you'll take';
- in old weak verbs ending in -jan the last consonant was palatalized, and the letter -j- is present in all forms, in contrast to older stages of the language, where it disappeared in some forms, cf. OB. xausida 'heard' (from xausjan) and NB. xouzjda (from xouzjen).
Declension paradigm also underwent significant changes.
- All inanimate nouns, including words denoting abstract ideas, natural phenomena, body parts, plants and mushrooms, food and drinks, tools and many other things, became Neuter, losing their specific Masculine or Feminine endings. It is worth noting that most animals (with the notable exception of the word deuz 'animal') preserved their gender.
- Old Dative came to be used with most of the prepositions, thus forcing the Genitive case out of the language. In Middle Burgundian, Genitive was only used after preposition af 'of'; later on, Dative came to be used even after this preposition. In modern language old Genitive is preserved in some archaic set phrases like Gudis vilja 'God's will' etc.
- The Nominative ending -s was reinterpreted as Masculine marker, so it was lost in Neuter nouns (including those that used to be Masculine or Feminine, like dags 'day' and naxts 'night') and added to some Masculine words were it wasn't present earlier, e.g. brodrs 'brother' vs. older brodar.
- Masculine and Feminine nouns changed their old Nominative plural ending -os for adjectival -i (from earlier -ai), while old -os ending (now -as) became an Accusative marker, by analogy with the Neuter gender, employing Nominative -a in the Accusative. The use of the adjectival ending might have been triggered by the similarly sounding endings in Slavic languages and Latin.
- Vowels forming declensional endings of nouns and adjectives underwent some changes, most notably -o > -a (tuggo 'tongue' > tunga, windros 'eyelashes' > vindras) and -ai > -i (mildai leudos'kind people' > mildi leudi, wibai '(to) the woman' > vibi). Thus, Feminine nouns ending in -a may belong to two different declensions in the modern language, e.g. viba 'woman' (Dative vibi), but meurja 'cockroach' (Dative meurjin).
Pronominal system was also modernized. Firstly, possessive pronouns lost their declension, so they are unchangeable in the modern language. Secondly, a whole paradigm of interrogative, demonstrative and relative pronouns and adverbs was devised, similar to that present in Japanese (da-re 'who', a-re 'he, she', ko-re 'this', so-re 'that' etc.) The stems' meanings are as follows: þ- stands for the close axis of demonstrative pronouns, jen- stands for the far axis, j- has the relative meaning, and p- forms interrogative words, e.g. þar 'here', jenar 'there', jar 'where (relative)', par 'where?'. This system wasn't present in the oldest stages of the language's development, but it had developed by the end of the Middle Burgundian stage.
In verbs, Burgundian lost several sets of forms, including all synthetic passive forms (nimada 'is taken', nimaidau 'let it be taken' etc.), past optative forms (nemi 'if it had been taken'), and the remains of the dual number (although they are absent as such even from the oldest stages of Burgundian).
The conjugation paradigm, though quite complicated today, also underwent simplification and modification. These processes include the following changes:
- old optative/subjunctive acquired the meaning of the future tense, thus ik nimou now basically means 'I'll take', and not 'I would take', although such forms are still used to express subjunctive mood;
- plural endings of the past tense of weak verbs were simplified, so old forms -idedum, -idedud, -idedun all changed into a uniform ending -edu (thus xausidedum 'we heard' became xouzjedu); in other tenses, however, the forms are distinct, e.g. nimaim 'we'll take' vs. nimait 'you'll take';
- in old weak verbs ending in -jan the last consonant was palatalized, and the letter -j- is present in all forms, in contrast to older stages of the language, where it disappeared in some forms, cf. OB. xausida 'heard' (from xausjan) and NB. xouzjda (from xouzjen).
Declension paradigm also underwent significant changes.
- All inanimate nouns, including words denoting abstract ideas, natural phenomena, body parts, plants and mushrooms, food and drinks, tools and many other things, became Neuter, losing their specific Masculine or Feminine endings. It is worth noting that most animals (with the notable exception of the word deuz 'animal') preserved their gender.
- Old Dative came to be used with most of the prepositions, thus forcing the Genitive case out of the language. In Middle Burgundian, Genitive was only used after preposition af 'of'; later on, Dative came to be used even after this preposition. In modern language old Genitive is preserved in some archaic set phrases like Gudis vilja 'God's will' etc.
- The Nominative ending -s was reinterpreted as Masculine marker, so it was lost in Neuter nouns (including those that used to be Masculine or Feminine, like dags 'day' and naxts 'night') and added to some Masculine words were it wasn't present earlier, e.g. brodrs 'brother' vs. older brodar.
- Masculine and Feminine nouns changed their old Nominative plural ending -os for adjectival -i (from earlier -ai), while old -os ending (now -as) became an Accusative marker, by analogy with the Neuter gender, employing Nominative -a in the Accusative. The use of the adjectival ending might have been triggered by the similarly sounding endings in Slavic languages and Latin.
- Vowels forming declensional endings of nouns and adjectives underwent some changes, most notably -o > -a (tuggo 'tongue' > tunga, windros 'eyelashes' > vindras) and -ai > -i (mildai leudos'kind people' > mildi leudi, wibai '(to) the woman' > vibi). Thus, Feminine nouns ending in -a may belong to two different declensions in the modern language, e.g. viba 'woman' (Dative vibi), but meurja 'cockroach' (Dative meurjin).
Pronominal system was also modernized. Firstly, possessive pronouns lost their declension, so they are unchangeable in the modern language. Secondly, a whole paradigm of interrogative, demonstrative and relative pronouns and adverbs was devised, similar to that present in Japanese (da-re 'who', a-re 'he, she', ko-re 'this', so-re 'that' etc.) The stems' meanings are as follows: þ- stands for the close axis of demonstrative pronouns, jen- stands for the far axis, j- has the relative meaning, and p- forms interrogative words, e.g. þar 'here', jenar 'there', jar 'where (relative)', par 'where?'. This system wasn't present in the oldest stages of the language's development, but it had developed by the end of the Middle Burgundian stage.