Appendix:Proto-Slavic verbs

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Proto-Slavic language #Conjugation

See also: Appendix:List of Proto-Slavic verbs

Verbs in Proto-Slavic closely resembled those of attested Old Church Slavonic. They descended from the Proto-Indo-European verbal system, but had been simplified and altered substantially.

There were three tenses: present, imperfect and aorist. There were scarcely any remnants of the perfect, but the verb *věděti (“to know”) preserved a few traces. All moods except for the indicative and imperative (from the PIE optative) had disappeared. No voice was distinguished; all verbs were grammatically active. However, there were five participles: present active and passive, past active and passive, and resultative.

Slavic verbs developed a new system of aspect independent of the Indo-European aspectual system. In this system, verbs are inherently perfective (completed) or imperfective (incomplete, ongoing). Various pairs of perfective and imperfective verbs existed, with widely varying means of derivation. Some used prefixes to derive one from the other, some used different conjugational suffixes. Some pairs were suppletive and had equivalent verbs with different roots, and some had more than one counterpart. A number of verbs stood "alone" and had no counterpart at all. All in all, this system resembled that of early Proto-Indo-European, in which many roots had only one or two aspect stems and a few had more than one for the same aspect.

Stem

Proto-Slavic verbs generally have two stems, which are the base from which all other forms are created.

Verbal noun	Infinitive	Supine	L-participle
1^{(2: C[lr])}	0	0	1^{(2: C[lr])}

	Participles
Tense	Past	Present
Passive	1^{(2: C[lr])}	2
Active	1^{(2: C[lr], V[ǫę])}	2

	Aorist			Present
Person	1st	2nd	3rd	1st	2nd	3rd
Singular	1			2
Dual
Plural
	Imperfect			Imperative
Person	1st	2nd	3rd	1st	2nd	3rd
Singular	2^{(1: -a, -ě)}			2
Dual
Plural

Examples for exceptional verb types:

C[lr]: *derti/*dьrǫtь, *dьrlъ (not **derlъ), *dьrtъ (not **dertъ), *dьrъ (not **dervъ)
V[ǫę]: *ęti/*jьmǫtь, *jьmъ (not **ęvъ)
-a: *pľьvati/*pľujǫtь, *pľьvaaxǫ (not **pľujaaxǫ)
-ě: *mьrzěti/*mьrzętь, *mьrzěaxǫ (not **mьržaaxǫ)

Verb classes

In Old Church Slavonic grammars, verbs are traditionally divided into four (or five) conjugation classes, depending on the present stem. However, this division ignores the formation of the infinitive stem. The following table shows the main classes of verbs in Proto-Slavic, along with their traditional OCS conjugation classes.

1st/e class (no suffix)
V/C	(V/C)	pluti/plovetь, pěti/pojetь
C	(C/C)	čisti/čьtetь
a/C	(Ca/C)	dьrati/deretь

2nd/ne class (suffix -n)
n	(n/n)	minǫti/minetь
V/n	(V/Vn)	stati/stanetь
C/n	(C/Cn)	dьrze/dьrznetь

4th/i class (suffix -i)
i	(i/i)	měsiti/měsitь
ě/i	(ě/i)	kypěti/kypitь
a/i	(a/i)	sъpati/sъpitь

3rd/je class (suffix -j)
C/j	(C/Cj)	melti/meľetь
V/Cj	(V/Cj)	žęti/žьňetь, děti/deďetь
V	(V/Vj)	obuti/obujetь, spěti/spějetь
a/V	(Ca/Vj)	pľьvati/pľujetь
ova/u	(ova/uj)	cělovati/cělujetь
ě	(ě/ěj)	cělěti/cělějetь
ja	(ja/jaj)	věťati/věťajetь
a	(a/aj)	padati/padajetь
a/j	(Ca/Cj)	*zьdati/ziďetь

Other
n-infix		byti/bǫdetь, sěsti/sędetь, leťi/lęžetь, obrěsti/obręťetь (see also: sęknǫti, sęťi, gręsti, žędati, pomęnǫti, rǫgati and *-nǫti)
V/d	(V/Vd)	byti/bǫdetь, jьti/jьdetь (see also: krasti, klasti, volsti, pędь)
xa/d	(Vxa/Vd)	jaxati/jadetь
C/v	(C/Cv)	pelti/pelvetь
V/v	(V/Vv)	žiti/živetь

Athematic verbs

Five verbs remained in Proto-Slavic which retained the athematic endings inherited from Proto-Indo-European. The present-tense endings lack their initial vowel and are attached directly to the root/stem, often with consonant changes. Also characteristic is the first-person singular present ending -mь instead of -ǫ. The following verbs are reconstructable:

*byti (“to be”) was suppletive and had a different root *es- in the present. It also had a unique set of forms to express future tense, based on a stem *bǫd-.
*dati (“to give”) had reduplication in the present tense, *dad-. This was not apparent in most forms, however, as the -d- usually dropped before the endings.
*ěsti (“to eat”)
*jьměti (“to have”) had the present stem *jьma-.
*věděti (“to know”) descended from a PIE perfect, and retained a unique ending -ě in the first-person singular present, next to -mь.

Consonant root stems

These verbs had no explicit stem-forming suffix; the stem was equal to the root and ended in a consonant. They were the descendants of PIE "thematic" verbs. This class was unproductive and contained only old inherited verbs. Several verbs also showed ablaut in the root or had other irregularities.

There were two subclasses:

Verbs with an infinitive in *-ti. The infinitive ending was attached directly to the root, causing the root-final consonant to either disappear or change in many cases.
Verbs with an infinitive in *-ati.

Irregularities:

*sesti (“to sit down”) and *leťi (“to lie down”) have an n-infix present: *sęd-, *lęg-.

Vowel root stems

These verbs were parallel to the consonant root stems. The root either ended in -j- itself, or ended in a vowel or liquid diphthong to which -j- was added. This class was likewise unproductive and a few verbs still displayed ablaut.

There were two subclasses, parallel to the consonant root stems:

Verbs with an infinitive in *-ti. The -j- was dropped in the aorist/infinitive stem, and the preceding vowel often underwent changes.
Verbs with an infinitive in *-jati.

Irregularities:

*děti (“to put”) had a present stem with reduplication: *deď- (< *ded-j-).

Verbs with suffix -aj- and -ěj-

These verbs have -aj- or -ěj- suffixed to the root. The -j- disappears in the infinitive/aorist stem, thus resulting in *-ati and *-ěti.

Verbs in -ěj- were mostly stative verbs. Remained somewhat productive.
Verbs in -aj- were originally denominative (from nouns) or factitive (from adjectives). The class remained very productive and regularly formed new imperfective verbs.

Verbs with suffix -a/j- and -ova/uj-

These two types have -j- and -uj- in the present stem, which alternate with the infinitive in *-ati and *-ovati. The former type remained somewhat productive but the latter type was especially productive and still remains so in the modern Slavic languages.

Verbs with suffix -n-

These verbs had presents in -n-, infinitives in *-nǫti. They descended from various verbs with -n- suffixes in PIE, including presumably the n-infix verbs. This class remained productive in Proto-Slavic to form new perfective verbs. There were some older imperfectives in this class as well.

There were two subclasses:

Verbs that retained -nǫ- in the aorist and participles.
Verbs that had no -nǫ- in the aorist or participles, retaining it only in the infinitive. The verb *stati (“to stand”) belonged here too, but had no suffix in the infinitive either.

Verbs with suffix -i-

These verbs had -i- in all forms, and had special endings in the present tense. This class was widely productive and usually remains so in modern Slavic languages. It contained a variety of Indo-European formations which merged, including causatives/iteratives and denominatives.

Verbs with suffix -ě/i- and -a/i-

These verbs had -i- in the present tense like the class above, but -ě- in the infinitive. It was a small class containing mostly stative verbs. There were some verbs in this group that have -a- preceded by a palatal consonant rather than -ě-. This was a result of the change ě > a when preceded by a palatal consonant, which happened during the Slavic period.

Alternations

Infinitive

Certain endings such as the infinitive *-ti (also suffix *-tь and supine *-tъ) often caused certain stem-final consonants to drop or change. Here is a list:

gti⇒ťi: *moťi/*moglъ
kti⇒ťi: *sěťi/*sěklъ
xti⇒ťi: *verťi/*vьrxlъ
zti⇒sti: *grysti/*gryzlъ
dti⇒sti: *vesti/*vedlъ
tti⇒sti: *mesti/*metlъ
bti⇒ti: *greti/*greblъ
pti⇒ti: *teti/*teplъ

Grade

V/C:

u/ov: *pluti/*plovetь, *kovati/*kujetь
ě/oj: *pěti/*pojetь

zero/e (o):

ьr/er (or): *dьrati/*deretь (*dorъ), *merti/*mьretь (*moriti), *verťi/*vьršetь (*vorxъ), *čьrpati/*čerpetь, [*mьrznǫti (*morziti)]
ьl/el (ol): *melsti/*mьlzetь (*molzъ)
ьn/en? ~ ę/ę (on/ǫ): *gъnati/*ženetь (*goniti), *orspęti/*orspьnetь (*orspona), *vęzati/*vęžetь (*vǫza)
ьm/em? (om): *žęti/*žьmetь, [(*lomiti)]
ь/i (ь/ě): *zьdati/*ziďetь, [*mьgnǫti (*měžiti)], *čisti/*čьtetь, *viti/*vьjetь (*povojь)

zero (o):

ъ (u): *sъxnǫti (*sušiti)

zero/o:

ъv/u: *pľьvati/*pľujetь
ъv/ov: *zъvati/*zovetь
ъm/om?: *dǫti/*dъmetь
ь?/ě: *smьjati/*smějetь, *zьjati/*zějetь (*zinǫti), *lьjati/*lějetь (*liti) (see also: *mijati, виꙗлица (vijalica), *pьjanъ, *sьjati, *rějati)

Other:

ъ/ju/u: (*bъděti / *bľusti / *buditi), (*plъtъ / *pľuťe / *pluti)