The verbal morphology of Armenian is fairly simple in theory, but is complicated by the existence of two main dialects, Eastern and Western. The following sketch will be a comparative look at both dialects.

Table of contents
1 Basic Forms
2 Tense/Mood/Aspect Structure
3 Putting It All Together

Basic Forms

Infinitive

The infinitive of Armenian verbs is formed with the stem, the theme vowel, and the affix -l:

sirel (to love) [= sir + e + -l]
EA kardal/WA gartal (to read) [= kard/gart + a + -l]

The endings reflect the number of conjugations possible. Western Armenian is conservative, retaining three conjugations: a, e, and i:

I: sirel (to love)
II: WA khôsil (to speak)
III: EA kardal/WA gartal (to read)

Eastern Armenian has collapsed WA conjugations I and II as /-el/:

khosel (to speak)

Stems

There are two main stems per verb, the present stem and past stem. For conjugations I/II, the past stem is identical to the present stem, which is basically the verb minus the theme vowel and ending:

sirel: pres/past sir-
khôsil/khosel: pres/past khôs-/khos-

The third conjugation has an augment, -ac' (sometimes -ec'):

kardal/gartal: pres. kard-/gart-, past kardac'-/gartac'-

Participles

The number and type of participles varies by dialect. The present and past participles are affixed to the past stem.

Both dialects have the following participles:

present in -ogh:
sirogh (loving)
EA khosogh/WA khôsogh (speaking)
EA kardac'ogh/WA gartac'ogh (reading)

Sometimes, this participle is used as an agentive noun:
usanogh (student), fr. usanel (to study)

future in -lu:
sirelu (loving)
EA khoselu/WA khôsilu (speaking)
EA kardalu/WA gartalu (reading)

Both dialects have a past passive participle, WA -adz/EA ac:

EA sirac/WA siradz (loved)
EA khosadz/WA khôsadz (spoken)
EA kardac'ac/WA gartac'adz (read)

Where the dialects differ is the past active participle. The Western Armenian participle is -er, for all conjugations:

sirer (loved)
khôser (spoken)
gartac'er (read)

Eastern Armenian has -el:
sirel (loved)
khosel (spoken)
kardac'el (read)

Eastern Armenian has two additional standard participles:

In addition to present -ogh, there is present -um:
sirum (loving)
khosum (speaking)
kardum (reading)

... and -lis:
sirelis (loving)
EA khoselis (speaking)
EA kardalis (reading)

Western Armenian has one additional participle, a future in -lik':

sirelik' (loving)
khôsilik' (speaking)
gartalik' (reading)

Tense/Mood/Aspect Structure

Introduction

Both dialects have the same number of moods, four (indicative, conditional, optative/subjunctive and imperative). The number of tenses varies by dialect. The aspect is divided roughly the same in both dialects, but the distribution is slighly different.

Indicative Tenses

The number of tenses of the indicative mood in both dialects are the following: present, imperfect, preterite, future. The actual usage varies by dialect.

Present
The present tense is dialect-specific. Eastern Armenian uses the -um participle with the present tense of "to be" (EA linel):

sirum, khosum, kardum + em
es
ê
enk'
ek'
en

Western Armenian uses a conjugated form of the verb preceded by the particle gë. The conjugated form of the verb corresponds to the verb class, i.e. e-vowel, i-vowel or a-vowel:

  Type I Type II Type III

gë + sirem
sires
sirê


sirenk'
sirêk'
siren

khôsim
khôsis
khôsi
khôsink'
khôsik'
khôsin

gartam
gartas
gartay*
gartank'
gartak'
gartan

*In Western Armenian, final /j/ in polysyllabic words is silent. It is given here as a transliteration. The form is pronounced [garta].

Examples:
(EA) Na girk'ë kardum ê (He is reading/reads the book)
(WA) An gë gartay kirk'ë. (ibid.)

Imperfect
The Eastern imperfect is the same construction, but substitutes the past tense of linel:

sirum, khosum, kardum + êi [pron. eyi]
êir [eyir]
êr [er]
êink' [eyink']
êik' [eyik']
êin [eyin]

The Western imperfect is gë plus the conjugated imperfect:

  Type I Type II Type III

gë + sirêi
sirêir
sirêr
sirêink'
sirêik'
sirêin

khôsêi
khôsêir
khôsêr
khôsêink'
khôsêik'
khôsêin

gartayi
gartayir
gartar
gartayink'
gartayik'
gartayin

Examples:
(EA) Nrank' im girk'ë kardum êin (They were reading/would read my book)
(WA) Anonk' gë gartayin im kirk'ë. (ibid.)

Future
The Eastern future tense is made with the future participle in -elu with the present tense of linel:

sirelu, khoselu, kardalu + em
es
ê
enk'
ek'
en

Western Armenian uses the present tense of the verb preceded by the particle bidi:

  Type I Type II Type III

bidi + sirem
sires
etc...

khôsim
khôsis
etc...

gartam
gartas
etc...

Examples:
(EA) Du ir girk'ë kardelu yes* (You will read his book)
(WA) Tun bidi gartas ir kirk'ë. (ibid.)

Note that due to the ending of the future participle, the forms em, es, enk', ek', en in EA are pronounced yem, yes, yenk', yek', yen.

Preterite
This tense goes by many different names in various grammars, but preterite comes closest to its actual function.

Both Eastern and Western Armenian use a synthetic preterite (i.e. the endings are attached directly to the verb). The preterite is formed by deleting the infinitive -l, then adding -c'i, -c'ir, etc... (see below). Note that WA 2nd conjugation in /i/ changes theme vowel to /e/ before adding the endings (in bold below), i.e. khôsil --> khôse-

(both) sirec'i
sirec'ir
sirec'
sirec'ink'
sirec'ik'
sirec'in 		(EA) khosec'i/(WA) khôsec'i
khosec'ir/khôsec'ir
etc... 		(EA) kardac'i/(WA) gartac'i
kardac'ir/gartac'ir
etc...

Examples:
(EA) Menk' mi girk' kardac'ink' (We read a book)
(WA) Menk' gartac'ink' kirk' më. (ibid.)

Optative

The optative mood (called the subjunctive in some grammars) in Armenian is identical in both dialects. There are two tenses: non-past (present, etc...) and past (perfect, etc ...).

Non-Past
The non-past optative is the simple "present" conjugated form, as compared to other Indo-European languages:

Eastern Western

Type I Type II Type I Type II Type III

sirem
sires
siri
sirenk'
sirek
siren

khosem
khoses
khosi
khosenk'
khosek'
khosen

kardam
kardas
karda
kardank'
kardak'
kardan

sirem
sires
sirê
sirenk'
sirêk'
siren

khôsim
khôsis
khôsi
khôsink'
khôsik'
khôsin

gartam
gartas
gartay*
gartank'
gartak'
gartan

*This form is pronounced [garta]

Past
The past optative is the simple "imperfect" conjugated form, as compared to other Indo-European languages:

Eastern Western

Type I Type II Type I Type II Type III

sirei
sireir
sirer
sireink'
sireik
sirein

khosei
khoseir
khoser
khoseink'
khoseik'
khosein

kardayi
kardayir
kardar
kardayink'
kardayik'
kardayin

sirêi
sirêir
sirêr
sirêink'
sirêik
sirêin

khôsêim
khôsêis
khôsêi
khôsêink'
khôsêik'
khôsêin

gartayi
gartayir
gartar
gartayink'
gartayik'
gartayin

A note about the /e/-conjugation and pronunciation:
In both dialects, there is a latent /j/ sound between the theme vowel and the ending. This means that sirei/sirêi is pronounced /sireji/. The /a/-conjugation has, in orthography (and in transliteration above), a written "y".

Conditional

The conditional in each dialect is distinct, based on how formed.

In Eastern Armenian, the non-past conditional is formed by affixing k- before the non-past optative: ksirem [pron. kësirem] (I would read), kkhosi (he would speak), etc. Become of this, Eastern Armenian also has a perfect (i.e. past) conditional with k- plus past optative: kkardayink' [pron. këkardayink'] (we would have read), etc.

An additional note: the Eastern conditional forms, with slight orthographic variation, are identical to the Western present and imperfect indicative forms (remember that EA /k/ = WA /g/):

(WA) An gë gartay kirk'ë. (He is reading/reads the book, prs.indic)
(WA) Anonk' gë gartayin im kirk'ë. (They were reading/would read my book, impf.indic)
but:
(EA) Na girk'ë kkarda (He would read the book [if ...], prs.cond)
(EA) Nrank' im girk'ë kkardayin (The would have read my book [if ...], pst.cond)

---

Western Armenian uses the imperfect of the verb preceded by the particle bidi:

  Type I Type II Type III

bidi + sirêi
sirêir
etc...

khôsêim
khôsêis
etc...

gartayi
gartayir
etc...

Western Armenian, therefore, has no explicit 'perfect' conditional the way Eastern Armenian does.

Imperative

The imperative mood in both dialects consists of the second person forms (singular and plural):

  Eastern Western

  Type I Type II Type I Type II Type III

du
duk'

sirir!
sirec'ek'!

khosir!
khosec'ek'!

karda!
kardac'ek'!

tun
tuk'

sirê!
sirec'êk'!

khôsê!
khôsec'êk'

garta!
gartac'êk'!

The Eastern forms have additional spoken alternates: siri!, khosi! instead of sirir!, khosir!; sirek'!, khosek'! instead of sirec'ek'!, khosec'ek'!.

Western Armenian also has a first person jussive form, which is usually classed as an imperative form. It is identical to the 1st person plural present form:

sirenk'! (Let's love!)
khôsink'! (Let's speak!)
gartank'! (Let's read!)

Other Forms

Necessitative Mood
Both dialects have what is known as the necessitative mood (also found in Turkish). Both dialects have a past and a non-past necessitative.

Eastern Armenian forms its necessitative by adding particle piti before the optative forms: piti sirem (I should/must love), piti khosenk' (we shoud/must speak); piti kardayin (they should have/must have read), etc.

Now note that the EA particle piti is orthographically identical to the WA particle bidi, meaning that the EA necessitative forms are identical in form to the WA future indicative and conditional:

(WA) An bidi gartay kirk'ë. (He will read the book, fut.indic)
(WA) Anonk' bidi gartayin im kirk'ë. (They would read my book [if ...], cond.)
but:
(EA) Na girk'ë piti karda (He should/must read the book, np.necess)
(EA) Nrank' im girk'ë piti kardayin (The should have read my book, pst.necess)

---

Western Armenian forms its necessitative with the lu future participle plus the forms of ëllal (to be):

Example (non-past jussive):
sirelu, khôsilu, gartalu + yem
yes
ê
yenk'
êk'
yen

In yet another formation, the Western forms correspond to Eastern forms with a completely different function, this time the Eastern future indicative (and future perfect indicative (see below)), and the Western non-past and past necessitative:

(EA) Na girk'ë kardalu ê (He will read the book, fut.indic)
(EA) Nrank' im girk'ë kardalu êin (They will have read my book, fut.perf.indic)
but:
(WA) An gartalu ê kirk'ë. (He should/must read the book, np.juss)
(WA) Anonk' gartalu êin im kirk'ë. (They should have read my book, pst.juss)

Eastern "Anterior" Forms
The Eastern dialect has, due to how the tenses are constructed, anterior forms which correspond to the perfect aspect.

The present anterior (also called the perfect) is formed with the past participle in l plus the present form of linel (to be): sirel em (I have loved), khosel ê (he has spoken), kardac'al en (they have read), etc.

The past anterior (pluperfect) is the l-past participle plus the imperfect forms of linel: sirel em (I had loved), khosel ê (he had spoken), kardac'al en (they had read), etc.

The future anterior (future perfect) is the lu-future participle plus the imperfect of linel: sirelu êi (I will have loved), khoselu êr (he will have spoken), kardalu êin (they will have read), etc.

Putting It All Together

Here are two tables, showing the full conjugation of each dialect's verb paradigms: Eastern, Western.

Irregular verbs for both dialects will be dealt will at a later date...