Old Church Slavonic grammar


Old Church Slavonic is an inflectional language with moderately complex verbal and nominal systems.

Nouns

The nominal case category distinguishes 7 cases for nouns, 6 for pronouns and adjectives :
Abbr.Case
NNominative
GGenitive
DDative
AAccusative
VVocative
LLocative
IInstrumental

Noun syntax

Number

Old Church Slavonic has three numbers: singular, dual, and plural.
The dual, and not the plural, is used when for nouns that are two. Nouns found in natural pairs, such as eyes, ears, and hands, are only found rarely in the plural. Due to its consistent use in all Old Church Slavonic texts, it appears to have been a living element of the language. The dual also affects adjectives and verbs in addition to nouns.

Nominative case

The nominative is used for the subject of a sentence, but it is only distinguished from the accusative in the masculine plural and the feminine singular, excluding the i-declension. Unlike in most modern Slavic languages, the nominative is also typically used for the complement of verbs meaning "to be". It is also used with verbs of naming and calling, but the accusative is also used for these verbs.

Accusative case

The accusative case is used for the direct object of a sentence with transitive verbs. For the masculine o/jo declension, the accusative singular for "an adult, healthy, free male person" is often shown by the use of the endings of the genitive singular. The accusative is also used with nouns for a duration of time and a measure of distance. Old Church Slavonic makes more frequent use of the accusative case after negated infinitives and participles than other Slavic languages, and it is unclear if this is an innovation of Old Church Slavonic or an archaism.

Genitive case

When used with nouns, the genitive frequently denotes the possessor of another noun or "the whole of which the other noun is a part", among other meanings. It is also used frequently with the numerals after five, and with certain pronouns, in the form of the partitive genitive.
The genitive may be used as the complement of the 'verb to' to denote possession, and it replaces the nominative as the complement of 'to be' in impersonal sentences if the verb is negated. It is also used for the object of negated infinitives or participles, and for the objects of certain verbs. It is used after some adjectives, and for objects of comparison after adjectives in the comparative. When recording a date, the month is typically written in the genitive. Unlike other Slavic languages, there is no genitive of time.

Dative case

The dative case is used for the indirect object of a sentence. In addition, it is infrequently used to denote the goal of a motion, but this is more typically shown by using the preposition къ followed by the dative. It is also used for the objects of verbs of commanding, obeying, favoring, giving, saying, showing, showing, and promising, as well as for verbs meaning "to seem", and "to be similar to". Additionally, it can be used with nouns and adjectives, particularly in impersonal constructions. It can also be used for a "dative of advantage", showing for whom an action was performed, and as an "ethic dative" that shows "emphasis or emotional involvement". Moreover, the dative can also be used to show possession, typically showing a close relationship between the possessor and the thing possessed, in which form it can occur after the verb "to be" or adjoining the noun possessed. The dative is also used for the "dative absolute" construction, a type of subordinate clause, in which a participle, often with a noun subject, are both placed in the dative.

Instrumental case

The instrumental case can show the "instrument" by which an action was performed, mark "a part of the body or state of mind accompanying the action", and denote the manner in which something was performed. The instrumental can be used to denote measure following a comparison, how many times an action was performed with numerals, an instrumental of place showing over or through what a movement occurs, to denote the time of an action, to mean "in respect to" when use with verbs, adjectives, or other nouns, and to denote the cause of verb, among other meanings. It is also used to denote the agent in passive constructions.
The instrumental is also found rarely for the complement of the verb "to be". It is not found in this meaning in the oldest Old Church Slavonic texts, the Gospels, and only occasionally in later texts.

Locative case

The locative case is used to denote the location in which something occurs. It very rarely occurs without a preceding preposition. Without a preposition, it is only used with place names, as a "locative of place". Due to more frequent use of locatives of place in Old Russian and Old Czech, it is possible that this rarity is caused by Old Church Slavonic following Greek syntax. It is also used, again rarely, for the "locative of time" to denote "in" a certain time. The locative is also used as the object of a small number of verbs; as this construction is extremely rare in other Slavic languages it is most likely an archaic form.

Vocative case

The vocative is used instead of the nominative when a noun is used in isolation as an address or exclamation. Due to this case's constitent use in translations from Greek, which has no vocative, it is clear that it was productive part of the spoken language.

o-stems

-SingularDualPlural
Ngrad-ъgrad-agrad-i
Ggrad-agrad-ugrad-ъ
Dgrad-ugrad-omagrad-omъ
Agrad-ъgrad-agrad-y
Vgrad-egrad-agrad-i
Lgrad-ěgrad-ugrad-ěxъ
Igrad-omьgrad-omagrad-y

Nouns belonging to this declension class are generally masculines ending in in the nominative singular. The only exception are the nouns in that inflect as u-stem masculines.
Sometimes, in the accusative singular, the beginnings of a difference between an animate and inanimate subgender can be seen, as the genitive may occasionally be used instead of the accusative for animate objects.
Nouns with the suffix -an-in-ъ also belong to this declension class in the singular, but in the plural they lose the -in- interfix and conform to the consonantal paradigm.
-SingularDualPlural
Nvin-ovin-ěvin-a
Gvin-avin-uvin-ъ
Dvin-uvin-omavin-omъ
Avin-ovin-ěvin-a
Vvin-ovin-ěvin-a
Lvin-ěvin-uvin-ěxъ
Ivin-omьvin-omavin-y

Nouns belonging to this declension class are neuters ending in -o in the nominative singular. The only exception are the few neuters that are inflected as s-stems.

jo-stems

-SingularDualPlural
Nnož-ьnož-anož-i
Gnož-anož-unož-ь
Dnož-unož-emanož-emъ
Anož-ьnož-anož-ę
Vnož-unož-anož-i
Lnož-inož-unož-ixъ
Inož-emьnož-emanož-i

Nouns belonging to this declension class are masculines ending in preceded by a palatal in the nominative singular.
This paradigm encompasses nouns such as krai that don't appear to be ending in a palatal, but are in fact underlyingly combinations like krajь and so undergo this declension.
Nouns ending in agentive suffixes -tel-ь and -ar-ь also belong to this class.
-SingularDualPlural
Nmor-emor-imor-a
Gmor-amor-umor-ь
Dmor-umor-emamor-emъ
Amor-emor-imor-a
Vmor-emor-imor-a
Lmor-imor-umor-ixъ
Imor-emьmor-emamor-i

The jo-stem declension class encompasses neuters ending in -e.

a-stems

-SingularDualPlural
Nrǫk-ac-ěrǫk-y
Grǫk-yrǫk-urǫk-ъ
Dc-ěrǫk-amarǫk-amъ
Arǫk-ǫc-ěrǫk-y
Vrǫk-oc-ěrǫk-y
Lc-ěrǫk-urǫk-axъ
Irǫk-ojǫrǫk-amarǫk-ami

Nouns belonging to this declension class are feminines ending in -a preceded by a hard, non-palatal consonant.
Also belonging to this paradigm are the rare masculines ending in -a.

ja-stems

-SingularDualPlural
Nduš-aduš-iduš-ę
Gduš-ęduš-uduš-ь
Dduš-iduš-amaduš-amъ
Aduš-ǫduš-iduš-ę
Vduš-eduš-iduš-ę
Lduš-iduš-uduš-axъ
Iduš-ejǫduš-amaduš-ami

Noun belonging to this declension class are feminines ending in -a preceded by a soft, palatal consonant.
This paradigm also encompasses feminines ending in -i, -ica and -ьni-, and also masculines ending in -a preceded by a palatal.

i-stems

-SingularDualPlural
Ngost-ьgost-igost-ьje
Ggost-igost-ьjugost-ьi
Dgost-igost-ьmagost-ьmъ
Agost-ьgost-igost-i
Vgost-igost-igost-ьje
Lgost-igost-ьjugost-ьxъ
Igost-ьmьgost-ьmagost-ьmi

Nouns belonging to this declension class are masculines ending in preceded by a hard, non-palatal consonant. The only exception are a limited number of such nouns belonging to the n-stem paradigm.
-SingularDualPlural
Nkost-ьkost-ikost-i
Gkost-ikost-ьjukost-ьi
Dkost-ikost-ьmakost-ьmъ
Akost-ьkost-ikost-i
Vkost-ikost-ikost-i
Lkost-ikost-ьjukost-ьxъ
Ikost-ьjǫkost-ьmakost-ьmi

Nouns belonging to the i-stem feminine declension are feminines ending in in the nominative singular.
The only exception is the noun krъvь which undergoes ъv-stem declension.

u-stems

-SingularDualPlural
Ndom-ъdom-ydom-ove
Gdom-udom-ovudom-ovъ
Ddom-ovidom-ъmadom-ъmъ
Adom-ъdom-ydom-y
Vdom-udom-ydom-ove
Ldom-udom-ovudom-ъxъ
Idom-ъmьdom-ъmadom-ъmi

Nouns belonging to this declension are a rather small group of masculines: činъ, domъ, ledъ, medъ, mirъ, polъ, sanъ, synъ, volъ, vrъxъ.

ū-stems

-SingularDualPlural
Ntyk-ytykъv-itykъv-i
Gtykъv-etykъv-utykъv-ъ
Dtykъv-itykъv-amatykъv-amъ
Atykъv-ьtykъv-itykъv-i
Vtyk-ytykъv-itykъv-i
Ltykъv-etykъv-utykъv-axъ
Itykъv-ьjǫtykъv-amatykъv-ami

Nouns belonging to the ū-stem declension are: buky, brady, cěly, crьky, horǫgy, loky, ljuby, neplody, prěljuby, smoky, svekry, žrьny, kry.

n-stems

-SingularDualPlural
Nkam-ykamen-ikamen-e
Gkamen-ekamen-ukamen-ъ
Dkamen-ikamen-ьmakamen-ьmъ
Akamen-ьkamen-ikamen-i
Vkam-ykamen-ikamen-e
Lkamen-ekamen-ukamen-ьxъ
Ikamen-ьmьkamen-ьmakamen-ьmi

Nouns belonging to this declension class are the following masculines: dьnь, jely, jęčьmy, kamy, kory, plamy, remy, sęženь, stepenь.
-SingularDualPlural
Nplem-ęplemen-iplemen-a
Gplemen-eplemen-uplemen-ъ
Dplemen-iplemen-ьmaplemen-ьmъ
Aplem-ęplemen-iplemen-a
Vplem-ęplemen-iplemen-a
Lplemen-eplemen-uplemen-ьxъ
Iplemen-ьmьplemen-ьmaplemen-y

Nouns belonging to this declension class are the following neuters: brěmę, čismę, imę, pismę, plemę, sěmę, slěmę, těmę, vrěmę.

s-stems

-SingularDualPlural
Nneb-onebes-ěnebes-a
Gnebes-enebes-unebes-ъ
Dnebes-inebes-ьmanebes-ьmъ
Aneb-onebes-ěnebes-a
Vneb-onebes-ěnebes-a
Lnebes-enebes-unebes-ьxъ
Inebes-ьmьnebes-ьmanebes-y

Nouns belonging to this declension class are the following neuters: čudo, divo, drěvo, kolo, nebo, tělo, slovo and also uxo and oko which have dual forms like i-stems.

t-stems

-SingularDualPlural
Ntel-ętelęt-ětelęt-a
Gtelęt-etelęt-utelęt-ъ
Dtelęt-itelęt-ьmatelęt-ьmъ
Atel-ętelęt-ětelęt-a
Vtel-ętelęt-ětelęt-a
Ltelęt-etelęt-utelęt-ьxъ
Itelęt-ьmьtelęt-ьmatelęt-y

The t-stem paradigm encompasses neuters denoting a young of an animal or human: otročę, agnę, kozьlę, kljusę, osьlę, ovьčę, telę, žrěbę etc.

r-stems

-SingularDualPlural
Nmat-imater-imater-i
Gmater-emater-umater-ъ
Dmater-imater-ьmamater-ьmъ
Amater-ьmater-imater-i
Vmat-imater-imater-i
Lmater-imater-umater-ьxъ
Imater-ьjǫmater-ьmamater-ьmi

r-stem feminines are the nouns mati and dъšti.

Pronouns

Personal pronouns

-SingularDualPlural
Nazъmy
Gmenenajunasъ
Dmьně nama namъ
Amene na ny
Lmьněnajunasъ
Imъnojǫnamanami

-SingularDualPlural
Ntyva vy
Gtebevajuvasъ
Dtebě vama vamъ
Atebe va vasъ
Lteběvajuvasъ
Itobojǫvamavami

Just as the first and second person pronouns, the third person pronoun is commonly used only in oblique cases. Nominative singular forms are not attested in the OCS corpus, and are reconstructed. In the East South Slavic dialectal area where OCS originated, a suppletive nominative singular stem of the demonstrative is used, elsewhere onъ, or very rarely .
By attaching the enclitic particle že to the forms of *i one obtains the relative pronoun: iže, ježe, jejuže, etc.
When following prepositions, these pronouns take a prothetic n-, hence kъ n'imъ instead of *imъ, na n'emь, etc. This is a remnant of final -m/n in the PIE prepositions *kom,
-Singular
N-
Gsebe
Dsebě
A
Lsebě
Isobojǫ

The reflexive pronoun has only singular oblique forms, which is the state of affairs inherited from PIE :wikt:Appendix:Proto-Indo-European *swé|*swé. The reflexive pronoun refers to the subject as a whole, and can be translated as English -self

Relative pronoun

As mentioned, the third person pronoun *i participates in the formation of the relative pronoun by appending the indeclinable enclitic že. Unlike the third person pronoun, however, the nominative case forms do occur. Similarly, a prothetic n- occurs when following prepositions, e.g., vъ n'ьže.

Interrogative pronoun and adjective

-Masculine,
Feminine
Neuter
Nkъtočьto
Gkogočeso
Dkomučesomu
Akogočьto
Lkomьčemь
Icěmьčimь

The interrogative pronoun has singular-only forms, with the masculine and feminine forms syncretized. Variant forms of čьto occurring in some of the oblique cases have been listed in parentheses.
The interrogative adjective, sometimes also labelled as the interrogative pronoun, also has some variant forms listed in parentheses.
The possessive interrogative adjective, sometimes also labelled as the possessive interrogative pronoun, follows the same declension.

Indefinite pronouns and adjectives

The interrogative pronouns kъto, čьto can also have the indefinite meanings of 'anybody', 'anything' respectively.
The prefix ně- imparts an indefinite meaning to the word to which it is attached: thus kъto becomes někъto, and čьto becomes něčьto. Similarly, the prefix ni- imparts a negative meaning: nikъto, ničьto. A prepositions may come between prefix and base word:

Adjectives

OCS adjectives can be in two forms: short and long, corresponding to indefinite and definite meaning respectively. The long and short forms of the adjective have distinct syntactical roles. In general the long form is used attributively, whereas the short form is predicative: чловѣкъ добръ 'a good man, man is good'; чловѣкъ добръіи 'the good man, the man who is good'. The short form is indefinite in meaning, 'man is good'. The combination of a short-form adjective with substantive is used when the signified entity is presented as new, without prior reference. Hence въ пєшть огн҄ьнѫ 'into a furnace, a fiery one'. The long form, by contrast, acts as a pointer and is definite, 'the good man'. The long-form adjective with substantive combination is used when the adjective presents a quality known to be associated with the substantive modified. Hence въ гєонѫ огн҄ьнѫѭ 'into hell the fiery'. The compound form is often rendered in English by a relative clause: 'into the hell which is fiery'. Adjectives used as substantives are themselves subject to the long and short form distinction. Again the long form refers to a substantive previously introduced or assumed known. Thus привѣшѧ къ н҄ємѹ слѣпа... и имъ слѣпаєго за рѫкѫ 'they brought to him a blind man... and having taken the blind man by the hand...'. In a sequence of coordinated participles, when used as substantives, it is typical for only the first to use the long form. The following substantives use the short form. Hence слъішѧи словєса моја и творѧ ја... 'he who hears my words and does them...'.
Indefinite adjectives are inflected as the corresponding nouns of the primary declension, e.g., novъ as rabъ, nova as žena, novo as selo, ništь as vračь, ništa as duša, nište as polje.
Definite adjectives are formed by suffixing to the indefinite form the anaphoric third-person pronoun , ja, je as shown in the table.
Nnovъ + i = novъjь > novyinova + ja = novaja
Gnova + jego = novajegonovy + jeję = novyję
Dnovu + jemu = novujemunově + jei = nověi
Anovъ + i = novъjь > novyinovǫ + jǫ = novǫjǫ
Lnově + jemь = novějemьnově + jei = nověi
Inovomь + imь = novъimь > novyimьnovojǫ + jejǫ = novojǫ, novǫjǫ

Nnovi + i = noviinovy + ję = novyję
Gnovъ + ixъ = novyixъnovъ + ixъ = novyixъ
Dnovomъ + imъ = novyimъnovamъ + imъ = novyimъ
Anovy + ję = novyjęnovy + ję = novyję
Lnověxъ + ixъ = novyixъnovaxъ + ixъ = novyixъ
Inovy + imi = novyiminovami + imi = novyimi

Adjective gradation

There are three levels of adjective gradation in OCS:
  1. Adjectives with falling tone on the root syllable:
  2. : dragъ − draž-ii, draž-e, draž-ьši ;
  3. : tęžьkъ − tęžii, tęže, tęžьši;
  4. : grǫbъ − grǫblii, grǫble, grǫblьši.
  5. Adjectives with rising tone on the root syllable:
  6. : novъ − nov-ěi, nov-ěje, nov-ěiši;
  7. : starъ − star-ěi, star-ěje, star-ěiši;
  8. : junъ − jun-ěi, jun-ěje, jun-ěiši.

    Declension of the comparative

Superlative

The superlative is formed:
  1. by adding the prefix nai- to the comparative base: naidražii, naitęžьši, naigrǫble;
  2. by combining the comparative form with the pronoun vьsego/vьsěxъ: nověi vьsego, dražii vьsěxъ.
The absolute superlative is formed:
  1. by adding the prefix prě- to the positive: prědragъ, prěnova, prěstaro;
  2. by using the adverb Ʒělo with the positive: Ʒělo dragъ, Ʒělo nova, Ʒělo staro.

    Numerals

Cardinals

Declension of cardinal numbers

Ordinals

All ordinals are inflected like the corresponding adjectives.

Verbs

Present

The present tense is formed by adding present-tense endings onto the present tense stem, which itself is sometimes hidden due to sound changes that have occurred in the past :
There are several classes of verbs:
1. e-type verbs add the interfix -e- to the present stem and the endings:
VerbSingularPluralDual
bosti
rešti

2. i-type verbs exhibit the same set of endings, but this time the interfix is -i-. In the first person singular one finds the processes of iotation and epenthesis :
VerbSingularPluralDual
xvaliti
ljubiti

3. The athematic verbs byti, dati, věděti, iměti and jasti form the present tense irregularly:
VerbSingularPluralDual
byti
věděti
iměti
jasti

One should distinguish the verbs iměti, imati and jęti. Exceptional is also the verb xotěti which exhibits iotation even though it's not an i-type verb.

Aorist

The aorist is used both to narrate individual events taking place at a specific time in the past, "without reference to other events taking place at the same time or subsequently" and to narrate the beginning or end of events of longer duration. Its most important function is to show that an event took place in the past, rather than to show that it is completed.
The aorist form of imperfective verbs is used instead of the perfective aspect in the case of verbs of motion and perception, as well as of the verbs iměti, and jasti. Imperfective verbs in the aorist are also used when an entire action is negated, and may be used for verbs of saying, although the usual form for "he said" is from a perfective verb, reče.

Asigmatic aorist

The asigmatic aorist was named after the loss of the phoneme /s/ in the inflection, i.e. there is no VsV > VxV change. Over time, the asigmatic aorist became increasingly marked as an archaic language feature and was eventually replaced by the other two aorist formations.
The asigmatic aorist was formed by adding to the infinitive stem of e-type verbs with stem ending in a consonant the following endings: -ъ, -e, -e; -omъ, -ete, -ǫ; -ově, -eta, -ete.
VerbSingularPluralDual
pasti 1. pad -ъ
2. pad -e
3. pad -e
1. pad -omъ
2. pad -ete
3. pad -ǫ
1. pad -ově
2. pad -eta
3. pad -ete
tešti 1. tek -ъ
2. teč -e
3. teč -e
1. tek -omъ
2. teč -ete
3. tek -ǫ
1. tek -ově
2. teč -eta
3. teč -ete
mošti 1. mog -ъ
2. mož -e
3. mož -e
1. mog -omъ
2. mož -ete
3. mog -ǫ
1. mog -ově
2. mož -eta
3. mož -ete
dvignǫti 1. dvig -ъ
2. dviž -e
3. dviž -e
1. dvig -omъ
2. dviž -ete
3. dvig -ǫ
1. dvig -ově
2. dviž -eta
3. dviž -ete

Sigmatic aorist

The sigmatic or s-aorist was formed in the following ways:
VerbSingularPluralDual
xvaliti 1. xvali -x -ъ
2. xvali
3. xvali
1. xvali -x -omъ
2. xvali -s -te
3. xvali -š -ę
1. xvali -x -ově
2. xvali -s -ta
3. xvali -s -te
tešti 1. těxъ
2. teče
3. teče
1. těxomъ
2. těste
3. těšę
1. těxově
2. těsta
3. těste
greti 1. grěsъ
2. grebe
3. grebe
1. grěsomъ
2. grěste
3. grěsę
1. grěsově
2. grěsta
3. grěste
bosti 1. basъ
2. bode
3. bode
1. basomъ
2. baste
3. basę
1. basově
2. basta
3. baste

New aorist

The new aorist is formed by suffixing to the infinitive stem of e-type verbs ending in a consonant the interfix -os- and onto it the endings -ъ, -, -; -omъ, -te, -ę; -ově, -ta, -te. Intervocalic sigma s changes into x.
The 2nd and the 3rd person singular forms are not attested and thus the asigmatic aorist forms are taken as a replacement.
VerbSingularPluralDual
krasti 1. krad -ox -ъ
2.
3.
1. krad -ox -omъ
2. krad -os -te
3. krad - -ę
1. krad -ox -ově
2. krad -os -ta
3. krad -os -te
rešti 1. rek -ox -ъ
2.
3.
1. rek -ox -omъ
2. rek -os -te
3. rek - -ę
1. rek -ox -ově
2. rek -os -ta
3. rek -os -te
iti 1. id -ox -ъ
2.
3.
1. id -ox -omъ
2. id -os -te
3. id - -ę
1. id -ox -ově
2. id -os -ta
3. id -os -te

Imperfect

The imperfect is used either for continuous or repeated actions in the past. It is typically used to form a background in a narration, and forms a contrast with the aorist and other verb forms: it often shows that an action took place at the same time as another. Actions in the imperfect are almost always incomplete, and the tense is typically only used with verbs in the imperfective aspect. Rarely, it can be formed with perfective verbs.
There are two ways of forming the imperfect:
1. If the infinitive stems ends in -a or , the interfix -ax- is appended and onto it, the endings of the asigmatic aorist: -ъ, -e, -e; -omъ, -ete, -ǫ; -ově, -eta, -ete.
VerbSingularPluralDual
glagolati 1. glagola -ax -ъ
2. glagola - -e
3. glagola - -e
1. glagola -ax -omъ
2. glagola - -ete
3. glagola -ax -ǫ
1. glagola -ax -ově
2. glagola - -eta
3. glagola - -ete
viděti 1. vidě -ax -ъ
2. vidě - -e
3. vidě - -e
1. vidě -ax -omъ
2. vidě - -ete
3. vidě -ax -ǫ
1. vidě -ax -ově
2. vidě - -eta
3. vidě - -ete

2. The other way of forming the imperfect, applying to all other verbal stems, is by adding onto the present stem the interfix -ěax- and onto it the endings of asigmatic aorist: -ъ, -e, -e; -omъ, -ete, -ǫ; -ově, -eta, -ete.
VerbSingularPluralDual
zъvati 1. zov -ě -ax -ъ
2. zov -ě - -e
3. zov -ě - -e
1. zov -ě -ax -omъ
2. zov -ě - -ete
3. zov -ě -ax -ǫ
1. zov -ě -ax -ově
2. zov -ě - -eta
3. zov -ě - -ete
bosti 1. bod -ě -ax -ъ
2. bod -ě - -e
3. bod -ě - -e
1. bod -ě -ax -omъ
2. bod -ě - -ete
3. bod -ě -ax -ǫ
1. bod -ě -ax -ově
2. bod -ě - -eta
3. bod -ě - -ete

Both of these imperfect formations often occur side by side in verbs with stem alternation:
In the texts of the OCS canon the forms are often contracted, so that ěax becomes ěx and aax becomes ax. An illustrating example is in Chernorizets Hrabar's famous work O pismenex "An Account of Letters":
Some forms exhibit sound changes, namely palatalization or iotation in front of ě, yat thus turning into a. The same applies if the stem ends in j which is then reduced in front of yat and yat again changes into a:
That the second form and not the first is the original one is confirmed by the imperfect paradigm of the verb byti:
VerbSingularPluralDual
byti1. běaxъ
2. běaše
3. běaše
1. běaxomъ
2. běašete
3. běaxǫ
1. běaxově
2. běašeta
3. běašete

Participles

Present active participle

The present active participle is formed by adding the following endings to the present stem:
1. e-type verbs and athematic verbs:
2. e-type verbs whose present stem ends in a palatal:
3. i-type verbs:
The present passive participle is formed by suffixing to the present stem the endings -o/e/i + m + ъ/a/o :
1. e-type verbs and athematic verbs:
2. e-type verbs whose stem ends in a palatal:
3. i-type verbs:
The past active participle is formed by suffixing to the infinitive stem the following endings:
1. e-type verbs and athematic verbs:
2. i-type verbs exhibit epenthetic v, which eliminates hiatus:
The latter i-type verbs have twofold forms of this participle - the mentioned one of older origin, and a newer one which arose due to analogical leveling:
3. Verbs with liquid metathesis form this participle from its older stem form:
4. Irregular participles:
The l-participle is formed by adding to the infinitive stem the interfix -l- and the endings ъ/a/o. If the stem ends in -t or -d, this consonant is dropped.
The past passive participle is formed by suffixing to the infinitive stem the following endings:
1. Verbs with stem ending in a consonant, -y or -i:
2. Verbs with stem ending in -a or :
3. Verbs with stem ending in , -u, -i and :
Of the latter verbs, those with stem ending in -i.

Compound tenses

Perfect

The perfect is formed by combining the l-participle with the imperfective present forms of the auxiliary verb byti.
The pluperfect can be formed in multiple ways, by combining the l-participle with the perfect, imperfect or aorist formation of the auxiliary verb byti.
The future tense is usually expressed using the present tense form of the perfective verb. Imperfective verbs form the future tense by combining the auxiliary verb and the infinitive.
The future perfect is formed by combining the l-participle with the perfective present of the auxiliary verb byti.
The conditional modal formation is formed by combining the l-participle with special modal forms of the auxiliary verb byti :
An alternative conditional is formed with the perfective aorist forms of byti:

Primary adverbs

These are original adverbs with difficult to guess etymology and origin.

Pronominal adverbs

Pronominal adverbs are derived by suffixing pronouns :
Nominal adverbs are derived from nominals or turn by conversion to adverbs which are in fact inflective lexemes with adverbial semantics.
Modal adverbs are created with the suffixes -o or , with no difference in meanings between suffixes, although some adverbs have only the forms in -o, and some in .
Modal adverbs could also be formed deadjectivally by means of the interfix -ьsk- and the ending -y.
Adverbs could also be formed with the suffix and are by origin probably inherited Proto-Slavic accusative forms.
Frequently occurring are the adverbialized a-stem instrumentals such as jednьnojǫ and also adverbially used oblique cases.
Locative adverbs are by origin mostly petrified locative case forms of nouns: gorě, dolě, nizu, and the same can be said for temporal adverbs: zimě, polu dьne.

Prepositions

Primary prepositions

The primary and non-derived prepositions are of PIE and PSl. heritage:
The secondary prepositions are derived from adverbial expressions: vьslědъ from vь slědъ, prěžde is a comparative form of prědъ etc.

Conjunctions and particles

Conjunctions and particles are not easily separable because they sometimes function as an intensifier, and sometimes as a conjunction.