Indo-European copula

A feature common to all Indo-European languages is the presence of a verb corresponding to the English verb to be. Though in some languages it is vestigial, it is present nonetheless in atrophied forms or derivatives.

General features

This verb has two basic meanings. In a less marked context it is a simple copula (I'm tired; That's a shame!), a function which in non-Indo-European languages can be expressed quite differently. In a more heavily marked context it expresses existence (I think therefore I am); the dividing line between these is not always easy to draw. Some languages have shared these functions between several verbs: Irish, Spanish and Persian all have multiple equivalents of to be, making a variety of distinctions. Many Indo-European languages also use the conjugations of the verb "to be" as an auxiliary for the formation of compound (periphrastic) tenses (I'm working; I was bitten). Other functions vary from language to language. For example, although in its basic meanings, to be is a stative verb, English puts it to work as a dynamic verb in fixed collocations (You are being very annoying).

The copula is the most irregular verb in many Indo-European languages. This is partly because it is more frequently used than any other, and partly because Proto-Indo-European offered more than one verb suitable for use in these functions, with the result that the daughter languages, in different ways, have tended to form suppletive verb paradigms. This article describes the way in which the irregular forms have developed from a series of roots.

The Proto-Indo-European [PIE] roots

*h₁es-

The root *h₁es- was certainly already a copula in Proto-Indo-European. The e-grade (see Indo-European ablaut) is found in such forms as English is, Irish is, German ist, Latin est, Sanskrit asti, while the zero grade produces forms beginning with /s/, like German sind, Latin sumus, Vedic Sanskrit smas, etc. In PIE, *h₁es- was an athematic verb in -mi; that is, the first person singular was *h₁esmi; this inflection survives in English am, Persian am, Sanskrit asmi, Old Church Slavonic есмь (esmĭ), etc.

This verb is generally reconstructed for Proto-Indo-European thus:^[1]

Person	Present indicative	Imperfect indicative	Subjunctive	Optative	Imperative
1st singular	*h1és-mi	*h1és-m̥	*h1és-oh2	*h1s-iéh1-m	—
2nd singular	*h1és-i	*h1és	*h1és-esi	*h1s-iéh1-s	*h1és, *h1s-dʰí
3rd singular	*h1és-ti	*h1és-t	*h1és-eti	*h1s-iéh1-t	*h1és-tu
1st dual	*h1s-uós	*h1s-ué	*h1és-owos	*h1s-ih1-wé	—
2nd dual	*h1s-tés	*h1s-tóm	*h1és-etes	*h1s-ih1-tóm	*h1s-tóm
3rd dual	*h1s-tés	*h1s-tā́m	*h1és-etes	*h1s-ih1-tā́m	*h1s-tā́m
1st plural	*h1s-m̥ós	*h1s-m̥é	*h1és-omos	*h1s-ih1-mé	—
2nd plural	*h1s-té	*h1s-té	*h1és-ete	*h1s-ih1-té	*h1s-té
3rd plural	*h1s-énti	*h1s-énd	*h1és-onti	*h1s-ih1-énd	*h1s-éntu

*bʰuH-

The root *bʰuH- or *bʰuh₂- (which did not have ablaut variations in the protolanguage^[2]) probably meant 'to grow', but also 'to become'. This is the source of the English infinitive be and participle been (Germanic participles have the suffix in -an). Also, for example, the Scottish Gaelic "future" tense bithidh; the Irish imperative bí, past bhí and future beidh; and the Slavic infinitive, etc. for example Russian быть (byt’). PIE *b^h becomes Latin /f/, hence the Latin future participle futūrus and perfect fuī; Latin fīō 'I become' is also from this root, as is the Greek verb φύω (phúō), from which physics and physical are derived.

This verb can be reconstructed as follows:^[1]

Person	Indicative	Subjunctive	Optative	Imperative
1st singular	*bʰúH-m	*bʰúH-oh2	*bʰuH-yéh1-m	—
2nd singular	*bʰúH-s	*bʰúH-esi	*bʰuH-yéh1-s	*bʰúH, *bʰuH-dʰí
3rd singular	*bʰúH-t	*bʰúH-eti	*bʰuH-yéh1-t	*bʰúH-tu
1st dual	*bʰuH-wé	*bʰúH-owos	*bʰuH-ih1-wé	—
2nd dual	*bʰuH-tóm	*bʰúH-etes	*bʰuH-ih1-tóm	*bʰuH-tóm
3rd dual	*bʰuH-tā́m	*bʰúH-etes	*bʰuH-ih1-tā́m	*bʰuH-tā́m
1st plural	*bʰuH-mé	*bʰúH-omos	*bʰuH-ih1-mé	—
2nd plural	*bʰuH-té	*bʰúH-ete	*bʰuH-ih1-té	*bʰuH-té
3rd plural	*bʰuH-énd	*bʰúH-onti	*bʰuH-ih1-énd	*bʰuH-éntu

*h₂wes-

The root *h₂wes- may originally have meant "to live".^[1] The e-grade is present in the German participle gewesen, the o-grade (*wos-) survives in English and Old High German was, while the lengthened e-grade (*wēs-) gives us English were. (The Germanic forms with /r/ result from grammatischer Wechsel.) See Germanic strong verb: Class 5.

*h₁er-

This has been claimed as the origin of the Old Norse and later Scandinavian languages' present stem: Old Norse em, ert, er, erum, eruð, eru; the second person forms of which were borrowed into English as art and are.^[3] It is also been seen as the origin of the Latin imperfect (eram, eras, erat) and future tenses (ero, eris, erit).

However, other authorities link these forms with *h₁es- and assume grammatischer Wechsel (/s/→/r/), although this is not normally found in the present stem. Donald Ringe argues that the copula was sometimes unaccented in Pre-Proto-Germanic, which would have then triggered the voicing under Verner's law.^[1] He explains the Germanic first person singular form *immi as such, deriving it from earlier *ezmi, since -zm-, but not -sm-, was assimilated to -mm- in Germanic (for which other evidence exists as well). Furthermore, the third person plural form *sindi (from PIE *h₁sénti) shows that this word, too, was unaccented. If the accent had been preserved, it would have become *sinþi, but that form is not found in any Germanic language. In this view, it is likely that stressed and unstressed varieties of the copula (with corresponding voiceless and voiced fricatives) existed side by side in Germanic, and the involvement of a separate root *h₁er- is unnecessary.

*steh₂-

The root *(s)teh₂- meant "to stand". From this root comes the present stem of the so-called "substantive verb" in Irish and Scottish Gaelic, tá and tha respectively. On the absence of the initial s- in Celtic, see Indo-European s-mobile.

In Latin, stō, stare retained the meaning "to stand", until local forms of Vulgar Latin began to use it as a copula in certain circumstances. Today, this survives in that several Romance languages (Galician-Portuguese, Spanish, Catalan) use it as one of their two copulae, and there is also a Romance tendency for a past participle derived from *steh₂- to replace the original one of the copula (this occurs in French, Italian and the main dialects of Catalan). See also Romance copula.

Although in Dutch, this verb retains its primary meaning of "stand", it is also used in an auxiliary-like function that only has a secondary meaning of "standing". For example, in ik sta te koken ("I stand (while) cooking"), the emphasis is on the act of cooking, and the implication of standing while doing so is only secondary, and may even be completely irrelevant. German "stehen" also exhibits a similar secondary meaning as a copula in certain locative phrases. For example, "Das Auto steht da" ("the car is over there" lit. "the car stands there"). When it is not a full copula (it can normally only be used as an auxiliary with another verb), it does have shades of meaning that resemble that of the Italian sto cucinando ("I am cooking"). The intransitive verbs zitten ("to sit"), liggen ("to lie") and lopen ("to walk/run") are used in similar ways.

In Swedish, which usually lacks gerund forms, the corresponding stå is often used similarly, along with sitta ("to sit"), ligga ("to lie") and gå ("to walk").

The resulting paradigms

Hittite

The Hittite verb "to be" is derived from the Indo-European root *h₁es-.

	Present indicative	Preterite indicative	Imperative
1st sg.	ēšmi	ešun	ēšlit ēšlut ašallu
2nd sg.	ēšši	ēšta	ēš
3rd sg.	ēšzi	ēšta	ēšdu
1st pl.	(ašweni)	ēšwen	–
2nd pl.	ēšteni	ēšten	ēšten
3rd pl.	ašanzi	ešer	ašandu

Indo-Iranian languages

Vedic Sanskrit

The Vedic Sanskrit verb as (to be) is derived from the Indo-European root *h₁es-.

Person	Present, Indicative, Active
	Singular	Dual	Plural
1st	asmi	svas	smas
2nd	asi	sthas	stha
3rd	asti	stas	santi

bhū (to be) is derived from Indo-European *b^huH-.

Person	Present, Indicative, Active
	Singular	Dual	Plural
1st	bhavāmi	bhavāvas(i)	bhavāmas(i)
2nd	bhavasi	bhavathas	bhavatha
3rd	bhavati	bhavatas	bhavanti

Persian

With regard to the function of the verb ‘to be’ as a copula, the most conspicuous feature of Modern Persian language is the evolution of an existential be, hast (exists), out of ast (is). In fact, when studying the forms and functions of ‘to be’, one might find certain characteristics specific to Persian that is worth pondering upon^[4]— i.e. even without considering the diachronic evolution of Modern Persian language and its relation to Ancient Iranian languages (such as Old Persian and Avestan) whose usage of the verb ‘to be’ seems more close to Sanskrit.
Paradoxically, despite the fact that Persian is apparently the only Indo-European language that has created an existential be out of the copula, it has simultaneously made an extreme use of the latter to produce a general paradigm for conjugating all Persian verbs.
Historically speaking, like most of Indo-European languages that make use of suppletive roots to denote ‘to be’, Persian integrates Proto-Indo-Eroupean (PIE) verbs *h₁es- (to be) and *b^huH (to grow> to become> to be). Hence, while Persian (Pers) infinitive būdan (to be) < PIE *b^huH forms the past stem of the verb (e.g. Pers būd- ‘was’) or acts as an auxiliary verb in formation of pluperfect of other verbs, its present tense is solely based on the derivatives of PIE *h₁es-. It is, in fact, from the declension of PIE *h₁es- (to be) that six present stems have been created and assigned to the 1st, 2nd, and 3rd person singular and plural to act as the present-tense conjugation of Pers būdan (to be), as shown in the following table.
(NB 1. Modern Persian nouns and pronouns have no grammatical gender; thus, all pronouns are neutral, e.g. the language does not distinguish between ‘he’ or ‘she’.
NB 2. In the conventional transliteration of Iranian languages: [x] is to be pronounced as ch in Bach or Loch Ness; [ā] as a in far; [ī] as ee in deed; [ū] as oo in food, [š] as sh in she, č as ch in chair, [ž] as j in déjà vu)

	Persian	CF. Classical Attic	English		Persian	English
1st Person	-am	εἰμί (eimi)	am		-īm	(we) are
2nd Person	-ī	εἶ (ei)	(thou) art		-īd	(you) are
3rd Person	ast (a)	ἐστί(ν) (esti(n))	is		-and	(they) are

As an example, in the following sentences, the present forms of the verb 'to be' are used as copulas or predicates:
______________ "man doxtar-e to am; īn barādar-e man ast (a or e); to pedar-e man ī "
______________ (‘I am your daughter; this is my brother; thou art my father.’)
Furthermore, as endings added to the stem of the verbs, these declensional forms have been grammatized to shape a general paradigm for the grammatical conjugation of all other verbs; as if any of these endings was once an auxiliary verb which evolved into an enclitic. Ironically, this generalized conjugational paradigm is also applied to the past tense of the very verb būdan (e.g. būd-am = literally: *‘(I) am was’→ ‘I was’; similarly būd-īm→ ‘we were’ etc.)
(NB. An old declensional suffix -ad is still used instead of ast for 3rd person singular in present-tense and subjunctive conjugation of Persian verbs).
However, what is linguistically notable, is the emergence of an existential be out of the copula, viz hast (exists) out of ast '(is). The evolution of this exceptional form, might go back to ancient Iranian languages, where ast could have two variants (cf. Avestan which has both as- and has- <PIE *h₁es- ‘be’). In the next phase, what we may call a pseudo-verb appeared, vis. the verb هستن hastan (to exist) has been analogically evolved from hast (exists) and has been conjugated like any other Persian verb (e.g. hast-am = literally: *‘(I) am existence’→ ‘I exist’).
Nevertheless, created out of a wrong re-analysis of hast (exists), the restrictions of this pseudo-verb would show up as soon as one tries to either find its past-tense and/or negate it. Then, hastan (to exist) will simply turn into the familiar past-tense or negation of the aforementioned verb būdan (e.g. būd-am ‘I was’ vs. na-būd-am ‘I was not’) which acts just as a copula and its existential meaning has to be inferred like English ‘to be’. We may therefore deduce that neither hast (exists) nor its derived pseudo-verb hastan (to exist) can be negated at all, unless reduced to copulas! In other words, we do not have *ni-hast (it does not exist), but *ni-ast> nīst (it is not) (despite the fact that there was once such a verb as (a)nihistan in Middle Persian (Pahlavi)). It is also worth mentioning that in the early stages of the Classic (Modern) Persian, ni-am was the only way to say ‘I am not’. However, following a secondary analogy (similar to hast [exists] → hastan [to exist]) a negative pseudo-verb nīstan (not to be) was invented. Therefore, the mirror image of the pseudo-verb hastan is not a negation of the existential verb, but just a simple negative copula formed from ast (is) → *ni-ast→ nīst (is not)> nīstan ‘not to be’ which, like hastan, has only present-tense (e.g. nīst-am ‘I am not’).
Finally, going back to the verb būdan, there is no doubt that it can only act as a copula, even if we look at its other forms which, as a heritage of the ancient Persian, has provided such moods as optative bād [<bovād ‘May it be!’], (wish to be), the potential (mood of probability) bov-ad (might be), and perhaps subjunctive/ conditional/ imperative bāš.
(NB. However, bāš may be from another PIE root *wes- cf. English was).^[5]
In this regards, we may notice that the third person forms of bāš whose infinitive bāšīdan is conjugated to produce conditional, or substantial mood, has a tendency to replace ast (is), although considered wrong by educated/cultured Persians (e.g. ū mādar mī-bāš-ad [She is (a) mother.] instead of simply ū mādar ast).
To summarize: As mentioned in the General Feature, the most significant point is that Persian grammar differentiates the marked or substantive form هست hast from copula است ast.^[6] Hast is used to express existence while ast expresses predication. Of course in colloquial Persian, hastan can be also used for emphasis to express predication in the present tense. In the past tense, the verb بودن būdan covers both meanings.

Strictly speaking, hastan is only a theoretical infinitive, not lexical. Therefore, būdan functions as the actual infinitive., used, for example, in past-tense as būd (was) and in present-tense modal bovad ‘it may be’. The circumstantial form of būdan is باش bāš, used for the imperative and subjunctive, e.g. اگر باشد agar bāsh-ad 'if it is'.

The forms ast (is) and hast (exists) have been derived from the Indo-European root *h₁es-, where būd (was) is derived from Indo-European *b^huH-.

Substantive verb HASTan (to exist) as an arbitrary infinitive conjugated with the aid of copula

The pseudo-verb هستن "hastan" (to exist) has only Simple Present Tense; in addition, it is truly and purely EXISTENTIAL only in the case of third person singular (hast). The fact is that the verb has been the product of this very case, as an "existential is", هست hast (she/ he/ it exists). For other persons the conjugation has to use enclitic copulas. These copulas are, in turn, derived from the declension of PIE *h1es- (to be); as if the predicative To BE has been an auxiliary verb turned into enclitic, to provide six endings for 1st/2nd/ 3rd person (singular & plural) [table above]. However, as it is said, the 3rd person singular has no ending in the case of "hastan". That is to say that the existential هست hast (exists), which is like the alter-ego of the copula است ast (is), takes no ending, while the present stem of all other verbs take an archaic ending -ad in their 3rd person singular.

Singular	Enclitic copula		Plural	Enclitic copula
هستم hastam = (I exist)	ام -am		هستيم hastīm = (we exist)	ايم -īm
هستى hastī = (thou existest)	اى -ī		هستيد hastīd = (you exist)	اید -īd
هست hast = (s/he/ it exists)	{اد ad}> Ø (a)		هستند hastand = (they exist)	اند -and

Simple Past Tense of BUDan (to be) as a double copula

The Simple Past Tense conjugation of the verb بودن būdan (to be) is in fact formed by a double-copula, in the sense that both the stem and the ending are copulas: the past stem of the verb بود būd- is derived from PIE *b^huH-, while the endings are from the suppletive form of PIE *h1es- (to be) with the exception of 3rd person singular which has zero ending for the all Persian verbs in the past-tense.

Singular	Enclitic copula		Plural	Enclitic copula
بودم būdam = (I was)	ام -am		بوديم būdīm = (we were)	ايم -īm
بودى būdī = (thou wast)	اى -ī		بوديد būdīd = (you were)	اید -īd
بود būd (būda) = (s/he/ it was)	Ø (a)		بودند būdand = (they were)	اند -and

Present Perfect of BUdan (to be) as a perfect double copula
The Present Perfect conjugation of the verb بودن būdan (to be) is a perfect double copula paradigm, in the sense that it is produced by addition of all enclitic copulas to the past participle of the verb: būde (been).

Singular	Enclitic copula		Plural	Enclitic copula
بوده ام būde-am = (I have been)	ام -am		بوده ايم būde-īm = (we have been)	ايم -īm
بوده اى būde-ī = (thou hast been)	اى -ī		بوده ايد būde-īd = (you have been)	اید -īd
بوده است būde ast (būde a) = (s/he/ it has been)	است ast (a)		بوده اند būde-and = (they have been)	اند -and

Greek

The Ancient Greek verb eimi (I am) is derived from the Indo-European root *h₁es-.

		Homeric Greek	Classical Attic	Modern Greek
Present indicative	1st sg. 2nd sg. 3rd sg. 1st pl. 2nd pl. 3rd pl.	εἰμί (eimi) εἶς, ἐσσί (eis, essi) ἐστί(ν) (esti(n)) εἰμέν (eimen) ἐστέ (este) εἰσί(ν), ἔασι (eisi(n), easi)	εἰμί (eimi) εἶ (ei) ἐστί(ν) (esti(n)) ἐσμέν (esmen) ἐστέ (este) εἰσί(ν) (eisi(n))	είμαι (ime) είσαι (ise) είναι (ine) είμαστε (imaste) είστε (iste) είναι (ine)
Preterite indicative	1st sg. 2nd sg. 3rd sg. 1st pl. 2nd pl. 3rd pl.	ἦα, ἔον (ēa, eon) ἦσθα, ἔησθα (ēstha, eēstha) ἦ(ε)ν, ἔην (ē(e)n, eēn) ἦμεν (ēmen) ἦτε (ēte) ἦσαν (ēsan)	ἦ(ν) (ē(n)) ἦς, ἦσθα (ēs, ēstha) ἦν (ēn) ἦμεν (ēmen) ἦστε, ἔατε (ēste, eate) ἦσαν ἔσαν (ēsan, esan)	ήμουν (imun) ήσουν (isun) ήταν (itan) ήμασταν (imastan) ήσασταν (isastan) ήταν (itan)
Subjunctive	1st sg. 2nd sg. 3rd sg. 1st pl. 2nd pl. 3rd pl.	ἔω (eō) ἔῃς, ἔοις (eēis, eois) ἔῃ(σι), ᾖσι(ν), ἔοι (eēi(si), ēisi(n), eoi)     ἔωσι(ν) (eōsi(n))	ὦ (ō) ᾖς (ēis) ᾖ (ēi) ὦμεν (ōmen) ἦτε (ēte) ὦσι(ν) (ōsi(n))
Optative	1st sg. 2nd sg. 3rd sg. 1st pl. 2nd pl. 3rd pl.	εἴην (eiēn) εἴης (eiēs) εἴη (eiē)   εἶτε (eite) εἶεν (eien)	εἴην (eiēn) εἴης (eiēs) εἴη (eiē) εἴημεν, εἶμεν (ei(ē)men) εἴητε, εἶτε (ei(ē)te) εἴησαν, εἶεν (eiēsan, eien)
Imperative	2nd sg. 3rd sg. 2nd pl. 3rd pl.	ἔσσο, ἴσθι (esso, isthi)   ἔστε (este)	ἴσθι (isthi) ἔστω (estō) ἔστε (este) ἔστων, ὄντων (estōn, ontōn)
Infinitive		εἶναι, ἔμ(μ)εν(αι) (einai, em(m)en(ai))	εἶναι (einai)
Participle		ἐών, ἐόντ- (eōn, eont-) fem. ἐοῦσα (eousa)	ὦν, ὄντ- (ōn, ont-) fem. οὖσα (ousa)

Note also that the participles are based on the full-grade stem ἐσ- in Homeric, according to Smyth.

Italic languages

Except for Latin, the older Italic languages are very scarcely attested, but we have in Oscan set (they are), fiiet (they become), fufans (they have been) and fust (he will be), and in Umbrian sent (they are). This section will explain Latin, and the Romance languages that have evolved from it.

In Spanish, Catalan, Galician-Portuguese and to a lesser extent, Italian there are two parallel paradigms, ser/èsser/essere from Latin esse "to be" on one hand, and estar/stare from Latin stare, "to stand" on the other.

For simplicity, the table below has only the full conjugation of the present tense, and the first-person singular forms of some other tenses.

	Latin		Old French		French	Spanish		Italian		Portuguese		Catalan		Romanian
Infinitive	esse	stāre	estre	ester	être	ser	estar	essere	stare	ser	estar	ser, ésser	estar	fi
Present indicative	sum es est sumus estis sunt	stō stās stat stāmus stātis stant	suis es est sommes estes sont	este estes este estons estez (=estets) estent	suis es est sommes êtes sont	soy eres es somos sois son	estoy estás está estamos estáis están	sono sei è siamo siete sono	sto stai sta stiamo state stanno	sou és é somos sois são	estou estás está estamos estais estão	sóc ets és som sou són	estic estàs està estem esteu estan	sunt eşti este suntem sunteţi sunt
Present subjunctive	sim	stem	sois	este	sois	sea	esté	sia	stia	seja	esteja	sigui	estigui	fiu
Preterite	fuī	stetī	fus	estai	fus	fui	estuve	fui	stetti	fui	estive	fui	estiguí	fusei / fui
Imperfect	eram	stābam	ier	estais	étais	era	estaba	ero	stavo	era	estava	era	estava	eram
Future	erō	stābō	serai	esterai	serai	seré	estaré	sarò	starò	serei	estarei	seré	estaré	voi fi
Past participle		statum		esté	été	sido	estado	stato	stato	sido	estado	estat / sigut (dialect)	estat	fost

In several modern Romance languages, the perfect is a compound tense formed with the participle as in English, but the old Latin perfect survives as a commonly used preterite in Spanish and Portuguese, and as a literary "past historic" in French, Italian and Catalan.

There is a tendency for a past participle derived from stare (or more specifically its supine, statum) to replace that of the main copula derived from esse. For example, the French participle été comes from statum.

For further information, see the main Romance copula article.

Germanic languages

Proto-Germanic retained the dual, but only in the first and second person.

	Proto-Germanic (reconstructed)		Gothic	Old Norse	Icelandic	Faroese	Nynorsk Norwegian	Norwegian Bokmål + Danish		Old Swedish	Swedish	Old English		English	Old High German	German	Luxem- burgish	Old Saxon	Dutch
Infinitive	*wesaną	*beuną?	wisan	vera	vera	vera	vera/vere	være		vara	vara	wesan	bēon	be	wesan	sein	sinn	wesan	zijn / wezen
Present indicative	*immi *izi *isti *izū *izudiz *izum *izud *sindi	*biumi *biusi *biuþi *beū? *biuþiz *beum *beuþ *biunþi	im is ist siju sijuts sijum sijuþ sind	em ert (est) er (es) – – erum eruð eru	er ert er – – erum eruð eru	eri ert er – – eru eru eru	er er er – – er er er	er er er – – er er er		æm/ær æst ær – – ærum ærin æru	är är är – – är (äro) är (ären) är (äro)	eom eart is – – sint sint sint	bēo bist biþ – – bēoþ bēoþ bēoþ	am art is – – are are are	bim, bin bist ist – – birum, bir(e)n birut, bir(e)t sint	bin bist ist – – sind seid sind	si(nn) bass ass – – si(nn) sidd si(nn)	bium bist is – – sind sind sind	ben – is – – zijn bent/zijt* zijn
Present subjunctive	*sijǭ *sijēs *sijē *sīw *sīþiz *sīm *sīþ *sīn	*biwjǭ? *biwjēs? *biwjē? *biwīw *biwīþiz *biwīm *biwīþ *biwīn	sijau sijais sijai sijaiwa sijaits sijaima sijaiþ sijaina	sjá sér sé – – sém séð sé	sé sért sé – – séum séuð séu	veri veri veri – – veri veri veri	– – (vere) – – – – –	– – (være) – – – – –		– – sē(i)/vari – – – – sēi(n)/vari(n)	– – (vare) – – – – –	sīe sīe sīe – – sīen sīen sīen	bēo bēo bēo – – bēon bēon bēon	be be be – – be be be	sī sīs(t) sī – – sīm, sīn sī(n)t sīn	sei sei(e)st sei – – seien seiet seien	– – sief – – – – –	sī sīs(t) sī – – sīn sīn sīn	zij – zij – – zijn zij zijn
Preterite indicative	*was *wast *was *wēzū *wēzudiz *wēzum *wēzud *wēzun		was wast was wēsu wēsuts wēsum wēsuþ wēsun	var varst var – – várum várið váru	var varst var – – vorum voruð voru	var vart var – – vóru vóru vóru	var var var – – var var var	var var var – – var var var		var vast var – – vārum vārin vāru	var var var – – var (voro) var (voren) var (voro)	wæs wǽre wæs – – wǣron wǣron wǣron		was wast was – – were were were	was wāri was – – wārum wārut wārun	war warst war – – waren wart waren	war waars war – – ware(n) waart ware(n)	was wāri was – – wārun wārun wārun	was – was – – waren was/waart* waren
Preterite subjunctive	*wēzį̄ *wēzīz *wēzī *wēzīw *wēzīdiz *wēzīm *wēzīd *wēzīn		wēsjau wēseis wēsi wēseiwa wēseits wēseima wēseiþ wēseina	væra værir væri – – værim værið væri	væri værir væri – – værum væruð væru	væri væri væri – – væri væri væri	– – – – – – – –	var var var – – var var var		– – vāri – – – – vāri(n)	vore vore vore – – vore vore (-en) vore	wǣre wǣre wǣre – – wǣren wǣren wǣren		were wert were – – were were were	wāri wārīs wāri – – wārīm wārīt wārīn	wäre wärest wäre – – wären wäret wären	wier wiers wier – – wiere(n) wiert wiere(n)	wāri wāris wāri – – wārin wārin wārin	ware – ware – – waren ware waren
Imperative	- *wes *wesadau - *wesadiz - *wisid *wesandau		- wis wisadau – wisats - wisiþ wisandau	- ver ver – – – verið verið	- vertu vertu – – - verið verið	- ver ver – – - verið verið	– ver ver – – – ver ver	- vær vær – – - vær vær		– - - – – – – -	- var var – – - var var	- wes wes – – - wesaþ wesaþ		- be be – – - be be	- wes wes – – - wesit wesit	- sei sei – – - seid seid	- - - – – - - -	- wes wes – – - wesad wesad	- wees - – – - weest -
Past participle	–		–	verit	verið	verið	vore (vori)	vært	været	varin	varit	–		been	giwesan	gewesen	gewiescht	(gi)wesan	geweest

Old English kept the verbs wesan and bēon separate throughout the present stem, though it is not clear that they made the kind of consistent distinction in usage that we find, for example in Spanish. In the preterite, however, the paradigms fell together. Old English has no participle for this verb.

The plural forms in Modern Swedish (indicated in brackets) were in common use in formal written language until the mid-20th century, but are now no longer in use except in deliberately archaising texts. The preterite subjunctive is also increasingly being replaced by the indicative.

• Dutch, like English, has abandoned the original second-person singular forms, replacing them with the second-person plural forms. However, while in English the old forms are still in limited and deliberately archaic use, in Dutch they have disappeared entirely and are no longer known or used at all. The forms listed in the plural are the historical plural forms, the 'jij' and 'gij' forms. Dutch formed a new plural pronoun 'jullie' with inflection similar to the 1st and 3rd person plural, but it would be redundant to list them here.

Slavic languages

	Proto-Slavic (reconstructed)	Old Church Slavonic	Ukrainian	Russian	Polish	Czech	Slovak	Slovenian	Serbo-Croatian	Bulgarian
Infinitive	*byti	бꙑти, byti	бути, buty	быть, byt'	być	být	byť	biti	biti
Present	*(j)esmĭ *(j)esi *(j)estĭ *(j)esvě *(j)esta *(j)este *(j)esmŭ *(j)este *sǫtĭ	ѥсмь, jesmĭ ѥси, jesi ѥстъ, jestŭ ѥсвѣ, jesvě ѥста, jesta ѥсте, jeste ѥсмъ, jesmŭ ѥсте, jeste сѫтъ, sǫtŭ	є[сь]м, je[ś]m єси, jesy є, je / єсть, jesť – – – (є)сьмо, (je)śmo (є)сте, (je)ste суть, suť	есмь, jesm' еси, jesi есть, jest' – – – есмы, jesmy есте, jeste суть, sut'	jestem, -m jesteś, -ś jest – – – jesteśmy, -śmy jesteście, -ście są	jsem jsi je – – – jsme jste jsou	som si je – – – sme ste sú	sem si je sva sta sta smo ste so	jesam, sam/budem* jesi, si/budeš jest, je/bude – – – jesmo, smo/budemo jeste, ste/budete jesu, su/budu	съм, səm си, si е, e – – – сме, sme сте, ste са, sə
Imperative	– *bǫdi *bǫdi *bǫděvě *bǫděta – *bǫděmŭ *bǫděte *bǫdǫ	– бѫди, bǫdi бѫди, bǫdi бѫдѣвѣ, bǫděvě бѫдѣта, bǫděta – бѫдѣмъ, bǫděmŭ бѫдѣте, bǫděte бѫдѫ, bǫdǫ	– будь, buď – – – – будьмо, buďmo будьте, buďte –	– будь, bud’ – – – – будем, budem будьте, bud’te –	– bywaj/bądź – – – – bywajmy/bądźmy bywajcie/bądźcie –	– buď – – – – buďme buďte –	– buď – – – – buďme buďte –	– bodi – bodiva bodita – bodimo bodite –	– budi (neka bude) – – – budimo budite (neka budu)	– бъди, bədi – – – – – бъдете, bədete –
Future	*bǫdǫ *bǫdešĭ *bǫdetĭ *bǫdevě *bǫdeta *bǫdete *bǫdemŭ *bǫdete *bǫdǫtĭ	бѫдѫ, bǫdǫ бѫдеши, bǫdeši бѫдетъ, bǫdetŭ бѫдевѣ, bǫdevě бѫдета, bǫdeta бѫдете, bǫdete бѫдемъ, bǫdemŭ бѫдете, bǫdete бѫдѫтъ, bǫdǫtŭ	буду, budu будеш, budeš буде, bude – – – будемо, budemo будете, budete будуть, buduť	буду, budu будешь, budeš' будет, budet – – – будем, budem будете, budete будут, budut	będę będziesz będzie – – – będziemy będziecie będą	budu budeš bude – – – budeme budete budou	budem budeš bude – – – budeme budete budú	bom, bodem boš, bodeš bo, bode bova, bodeva bosta, bodesta bosta, bodesta bomo, bodemo boste, bodeste bodo, bojo	budem budeš bude – – – budemo budete budu	ще бъда, šte bədə ще бъдеш, šte bədeš ще бъде, šte bəde – – – ще бъдем, šte bədem ще бъдете, šte bədete ще бъдат, šte bədət
Imperfect	*běaxŭ *běaše *běaše *běaxově *běašeta *běašete *běaxomŭ *běašete *běaxǫ	бѣахъ, běaxŭ бѣаше, běaše бѣаше, běaše бѣаховѣ, běaxově бѣашета, běašeta бѣашете, běašete бѣахомъ, běaxomŭ бѣашете, běašeте бѣахѫ, běaxǫ							bijah, b(j)eh bijaše, b(j)eše bijaše, b(j)eše – – – bijasmo, b(j)esmo bijaste, b(j)este bijahu, b(j)ehu	бях, bjah бе[ше], be[še] бе[ше], be[še] – – – бяхме, bjahme бяхте, bjahte бяха, bjahə
Aorist	*byxŭ *by(stŭ?) *by(stŭ?) *byxově *bysta *byste *byxomŭ *byste *byšę	бꙑхъ, byxŭ бꙑ(стъ), by(stŭ) бꙑ(стъ) by(stŭ) бꙑховѣ, byxově бꙑста, bysta бꙑсте, byste бꙑхомъ, byxomŭ бꙑсте, byste бꙑшѧ, byšę				bych bys by – – – bychom byste by		(bi) bi bi (bi) (bi) (bi) (bi) (bi) (bi)	bih bi bi – – – bismo biste biše	(бих, bih) (би, bi) (би, bi) – – – (бихме, bihme) (бихте, bihte) (биха, bihə)
Present active participle	*sy m. *sǫťi f. *sy n.	сꙑ, sy m. сѫщи, sǫšti f. сꙑ, sy n.								(същ, səšt m.) (съща, səšta f.) (също, səšto n.)
Future active participle	*bǫdy m. *bǫdǫťi f. *bǫdy n.	бѫдꙑ, bǫdy m. бѫдѫщи, bǫdǫšti f. бѫдꙑ, bǫdy n.	будучий, budučyj m. будуча, buduča f. будуче, buduče n.	будущий, buduščij m. будущая, buduščaja f. будущее, buduščeje n.	będący m. będąca f. będące n.	budoucí m. budoucí f. budoucí n.	budúci m. budúca f. budúce n.	bodoči m. bodoča f. bodoče n.	budući m. buduća f. buduće n.	(бъдещ, bədešt m.) (бъдещ, bədeštа f.) (бъдещо, bədeštо n.)
Past active participle	*byvŭ m. *byvŭši f. *byvŭ n.	бꙑвъ, byvŭ m. бꙑвъши, byvŭši f. бꙑвъ, byvŭ n.	бувший, buvšyj m. бувша, buvša f. бувше, buvše n.	бывший, byvšij m. бывшая, byvšaja f. бывшее, byvšeje n.	bywszy m. bywsza f. bywsze n.			bivši m. bivša f. bivše n.	bivši m. bivša f. bivše n.	(бивш, bivš m.) (бивша, bivša f.) (бивше, bivše n.)
Resultative participle	*bylŭ m. *byla f. *bylo n.	бꙑлъ, bylŭ m. бꙑла, byla f. бꙑло, bylo n.	був, buv m. була, bula f. було, bulo n.	был, byl m. была, byla f. было, bylo n.	był m. była f. było n.	byl m. byla f. bylo n.	bol m. bola f. bolo n.	bil m. bila f. bilo n.	bio m. bila f. bilo n.	бил, bil m. била, bila f. било, bilo n.

• In Russian, the present forms are archaic and no longer in common use, except for the third person forms, which are used in "there is/are" type phrases.
• In Serbo-Croatian the forms jesam, jesi, jeste and so on are used as the basic form of the Present Tense "to be" (i.e. I am, you are etc.), while the forms budem, budeš, bude etc. are used only for the formation of the Future Perfect.
• In Bulgarian, forms бъда, бъдеш, etc. are not used by themselves but only in compound forms (future ще бъда, subjunctive да бъда). In this respect they closely follow the usage (and non-usage) of prefective verbs. As such it has its own forms for the aorist (бидох, биде, биде, бидохме, бидохте, 'бидоха), the imperfect (бъдех, бъдеше, бъдеше, бъдехме, бъдехте, бъдеха) and the resultative participle (бъдел). Another verb - бивам with fully regular conjugation type III paradigm - completes an aspect triple: imperfective съм, perfective бъда, secondary imprefective бивам. The perfective aorist has lost its original meaning and is now used only to form the compound conditional mood (бих чел = I would read). All participles except the resultative participle (бил) have lost their function and are now used as regular adjectives with changed meanings (същ = same, бивш = previous, ex-, бъдещ = future).

Baltic languages

	Lithuanian	Latvian	Old Prussian
Infinitive	būti	būt
Present	esu, esmi (rare), būnu esi, būni (rare) yra, esti, esa (rare), būna esame, būname (rare) esate, būnate (rare) yra, esti (rare), esa (rare), būna (rare)	esmu, esu (vernacular) esi ir esam esat ir
Past simple	buvau buvai buvo buvome buvote buvo	biju biji bija bijām bijāt bija
Past active participle	buvęs (m. sg.) buvusi (f. sg.) buvę (m. pl.) buvusios (f. pl.)	bijis (m. sg.) bijusi (f. sg.) bijuši (m. pl.) bijušas (f. pl.)
Future	būsiu būsi bus būsime būsite bus	būšu būsi būs būsim būsiet, būsit būs
Imperative	– būk – būkime būkite –	– esi – būsim esiet –
Quotative		esot, būšot
Conditional	būčiau būtum būtų būtumėme būtumėte būtų	būtu

In Lithuanian, the paradigm būnu, būni, būna, etc. is not considered archaic or dialectal but rather a special use of the verb būti, to be, mostly used to describe repeated actions or states, or habits.

Celtic languages

In the Celtic languages there is a distinction between the so-called substantive verb, used when the predicate is an adjective phrase or prepositional phrase, and the so-called copula, used when the predicate is a noun.

The conjugation of the Old Irish and Middle Welsh verbs is as follows:

	Old Irish substantive verb	Old Irish copula	Middle Welsh
Present	(at)·tó (at)·taí (at)·tá (at)·taam (at)·taïd (at)·taat	am at is ammi adib it	wyf wyt yw, mae, taw, oes ym ych ynt, maen(t)
Preterite	·bá ·bá ·boí ·bámmar ·baid ·bátar	basa basa ba bommar unattested batar	buum buost bu buam buawch buant
Future	bia bie bieid, ·bia beimmi, ·biam bethe, ·bieid bieit, ·biat	be be bid bimmi unattested bit	bydaf bydy byd bydwn bydwch bydant

The forms of the Old Irish present tense of the substantive verb, as well as Welsh taw, come from the PIE root *stā-. The other forms are from the roots *es- and *bhū-. Welsh mae originally meant "here is" (cf. yma 'here').

Irish and Scottish Gaelic

In modern Gaelic, person inflections have almost disappeared, but the negative and interrogative are marked by distinctive forms. In Irish, particularly in the south, person inflections are still very common for the tá/bhí series.

^{[note 1]}

The verb bí

		Scottish Gaelic	Irish
Present	affirmative interrogative negative negative interrogative	tha a bheil chan eil nach eil	tá (1 táim, 2 táir, 3 tá, 1pl táimíd, 2pl (archaic) táthaoi, 3pl táid) an bhfuil níl (ní fhuil) nach bhfuil (1 fuilim, 2 fuilir, 3 fuil, 1pl fuilimíd-fuileam, 2pl (archaic) fuiltaoi, 3pl fuilid)
Past	affirmative interrogative negative negative interrogative	bha an robh cha robh nach robh	bhí (1 bhíos, 2 bhís, 3 bhí, 1pl bhiomair, 2pl bhíobhair, 3pl bhíodar) an raibh ní raibh nach raibh (1 rabhas, 2 rabhais, 3 raibh, 1pl rabhamair, 2pl rabhabhair, 3pl rabhadar)
Future	affirmative interrogative negative negative interrogative	bidh (or "bithidh") am bi cha bhi nach bi	beidh (1 bead, 2 beir, 3 beidh, 1pl beimíd, 2pl beidh sibh, 3pl beid) an mbeidh ní bheidh nach mbeidh

The copula

		Scottish Gaelic		Irish
		Before a consonant	Before a vowel	Before a consonant	Before a vowel
Present	affirmative interrogative negative negative interrogative	is		is an ní nach	is an ní nach
Past/Conditional	affirmative interrogative negative negative interrogative	bu		ba ar níor nár	b' arbh níorbh nárbh

^[7]

Gaelic (bh)eil and Irish (bh)fuil are from Old Irish fuil, originally an imperative meaning "see!" (PIE root *wel-, also in Welsh gweled, Germanic wlitu- "appearance", and Latin voltus "face"), then coming to mean "here is" (cf. French voici < vois ci and voilà < vois là), later becoming a suppletive dependent form of at-tá. Gaelic robh and Modern Irish raibh are from the perfective particle ro (ry in Welsh) plus ba (lenited after ro).

Modern Welsh

The present tense in particular shows a split between the North and the South. Though the situation is undoubtedly more complicated, King (2003) notes the following variations in the present tense as spoken (not as written according to the standard orthography):

		Affirmative (I am)		Interrogative (Am I?)		Negative (I am not)
		Singular	Plural	Singular	Plural	Singular	Plural
North	First person	dw	dan	ydw?	ydan?	(dy)dw	(dy)dan
	Second person	—, (r)wyt	dach	wyt?	(y)dach?	dwyt	(dy)dach
	Third person	mae	maen	ydy?	ydyn?	dydy	dydyn
South	First person	rw, w	ŷn, —	ydw?	ŷn?	(d)w	ŷn
	Second person	—, (r)wyt	ych	wyt?	ych?	—	(ych)
	Third person	mae	maen	ydy?, yw?	ŷn?	dyw	ŷn

Note that, for example, the spoken first person singular dw i'n is a contraction of the formal written yr ydwyf fi yn . The Welsh F /v/ is the fricative analogue of the nasal /m/, the PIE suffix consonsant for the first person singular.

		Affirmative (I am)		Interrogative (Am I?)		Negative (I am not)
		Singular	Plural	Singular	Plural	Singular	Plural
Preterite	First person	bues	buon	fues?	fuon?	fues	fuon
	Second person	buest	buoch	fuest?	fuoch?	fuest	fuoch
	Third person	buodd	buon	fuodd?	fuon?	fuodd	fuon
Imperfect	First person	roeddwn	roedden	oeddwn?	oedden?	doeddwn	doedden
	Second person	roeddet	roeddech	oeddet?	oeddech?	doeddet	doeddech
	Third person	roedd	roeddyn	oedd?	oeddyn?	doedd	doeddyn
Future	First person	bydda	byddwn	fydda?	fyddwn?	fydda	fyddwn
	Second person	byddi	byddwch	fyddi?	fyddwch?	fyddi	fyddwch
	Third person	bydd	byddan	fydd?	fyddan?	fydd	fyddan

Bod also has a conditional, for which there are two stems. The bas- stem is more common in the North, and the bydd- stem is more common in the South:

		Affirmative		Interrogative		Negative
		Singular	Plural	Singular	Plural	Singular	Plural
bydd-	First person	byddwn	bydden	fyddwn	fydden	fyddwn?	fydden?
	Second person	byddet	byddech	fyddet	fyddech	fyddet?	fyddech?
	Third person	byddai	bydden	fyddai	fydden	fyddai?	fydden?
bas-	First person	baswn	basen	faswn	fasen	faswn?	fasen?
	Second person	baset	basech	faset	fasech	faset?	fasech?
	Third person	basai	basen	fasai	fasen	fasai?	fasen?

Armenian

The Classical Armenian present tense derives from PIE *h₁es- (cf. sg. h₁esmi, h₁essi, h₁esti; 3rd pl. h₁s-énti).^[8]

	present
1st sg.	em
2nd sg.	es
3rd sg.	ē
1st pl.	enkʿ
2nd pl.	ēkʿ
3rd pl.	en

Albanian

The Albanian copula shows two distinct roots. The present jam ‘I am’ is an athematic root stem built from PIE *h₁es-. The imperfect continues the PIE imperfect of the same root but was rebuilt based on the 3rd person singular and plural. The perfect, on the other hand, comes from the thematic aorist of PIE *kʷelh₁- ‘turn’ (cf. Ancient Greek épleto ‘he turned’, Armenian eɫew ‘he became’, Old Irish cloïd ‘turns back, defeats’). Analogical or otherwise indirect reflexes are italicized below.

	PIE	present	PIE → PAlb	rebuilt	imperfect (NE Arvanitic)	imperfect (standard Alb)	PIE → PAlb	perfect
1st sg.	*h₁ésmi	jam	*h₁és-m̥ → *eham	*eśen	jeshë	isha	*kʷl-e-m̥ → *klen^†	qeshë, OAlb qeva
2nd sg.	*h₁ési	je	*h₁és → *eh	*eśeh	jeshe	ishe	*kʷl-e-s → *kleh	qe
3rd sg.	*h₁ésti	ishtë (dial.)	*h₁és-t → *eśt	*eśt	je	ish → ishte	*kʷl-e-to → *kleta	kle → qe
1st pl.	*h₁s-méi	jemi	*h₁s-m̥é → *emma/e	*eśema/e	jeshëmë	ishim	*kʷl-e-mé → *klema/e	qemë
2nd pl.	*esi (2nd sg.) + -ni	jeni	*h₁s-té → *eśtā	*eśetā	jeshëtë	ishit	*kʷl-e-té → *kletā	qetë
3rd pl.	*h₁s-nti	janë	*h₁s-énd → *eśend	*eśend	ishinë	ishin	*kʷl-e-nd → *klend	qenë

See also

• Grammatical conjugation

Notes

1. Colin Mark has suggested that the Scots Gaelic substantive verb forms can be treated as assertive forms of the copula;^[9] since the verb is in any case suppletive, this is a matter of perspective.

References

1. Ringe, Don (2006). A History of English: Volume I: From Proto-Indo-European to Proto-Germanic. Oxford: Oxford University Press. ISBN 9780199284139. Retrieved 9 February 2013.
2. Jasanoff, Jay (2003). Hittite and the Indo-European Verb. Oxford University Press. p. 112. ISBN 0-19-928198-X.
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8. Hrach K. Martirosyan, Etymological Dictionary of the Armenian Inherited Lexicon, s.v. “em” (Leiden: Brill, 2009), 255.
9. Colin Mark, Gaelic Verbs systemised and simplified, Savage (London & Edinburgh) 1986, p21ff.