Nouns have 3 animacy classes: Human is used for humans and powerful things Dead is used for dead humans, dead animals, some plants, and dangerous things Neuter is used for everything else Nouns decline in 4 declensions: The first declension has a nominative in -el and a vocative in -ero. The vocative stem is used for all but NOMNominative (case)
TRANS subject, INTR argument.SGSingular (number)
one countable entity and NOMNominative (case)
TRANS subject, INTR argument.PLPlural (number)
more than one/few

	SGSingular (number) one countable entity	DUDual (number) two	PLPlural (number) more than one/few
NOMNominative (case) TRANS subject, INTR argument	base (-el)	-ẽl	-eli
ACCAccusative (case) TRANS direct object; patient	-ers	-õrs	-eri
DATDative (case) indirect object; recipient, beneficiary, location	-erẍa	-erẍan	-eriṕa
GENGenitive (case) possessive	-al	-õl	-aldi
VOCVocative (case) 'O [addressee]'	base (-ero)	-erõ	-iro

Only one form, VOCVocative (case)
'O [addressee]'.DUDual (number)
two, undergoes assimilation, with all o's becoming õ's Let's see this on a noun. The noun is knijvel, with a vocative stem of knijvero.

	SGSingular (number) one countable entity	DUDual (number) two	PLPlural (number) more than one/few
NOMNominative (case) TRANS subject, INTR argument	knijvel	knijvẽl	knijveli
ACCAccusative (case) TRANS direct object; patient	knijvers	knijvõrs	knijveri
DATDative (case) indirect object; recipient, beneficiary, location	knijverẍa	knijverẍan	knijveriṕa
GENGenitive (case) possessive	knijval	knijvõl	knijvaldi
VOCVocative (case) 'O [addressee]'	knijvero	knijverõ	knijviro

As you can see, the nominative and vocative stems are the same for most first declension nouns. However, it will come into play in other declensions TO BE CONTINUED....

2nd Declension has a nominative stem ending in -ig, ẽg, or -ar. The vocative stem ends in -irf, and is used for everything but NOMNominative (case)
TRANS subject, INTR argument.SGSingular (number)
one countable entity and DATDative (case)
indirect object; recipient, beneficiary, location.SGSingular (number)
one countable entity. Irregular stems are commoner than in first declension.

	SGSingular (number) one countable entity	DUDual (number) two	PLPlural (number) more than one/few
NOMNominative (case) TRANS subject, INTR argument	base (-ig)	-or	-irg
ACCAccusative (case) TRANS direct object; patient	-ithe	-itho	-ite
DATDative (case) indirect object; recipient, beneficiary, location	base (-ig)	-urxo	-uj
GENGenitive (case) possessive	-ac	-acit	-acl
VOCVocative (case) 'O [addressee]'	base (-irf)	-er	-erf

Here's a table with dẽjig as an example:

	SGSingular (number) one countable entity	DUDual (number) two	PLPlural (number) more than one/few
NOMNominative (case) TRANS subject, INTR argument	dẽjig	dẽjor	dẽjirg
ACCAccusative (case) TRANS direct object; patient	dẽjithe	dẽjitho	dẽjite
DATDative (case) indirect object; recipient, beneficiary, location	dẽjig	dẽjurxo	dẽjuj
GENGenitive (case) possessive	dẽjac	dẽjacit	dẽjacl
VOCVocative (case) 'O [addressee]'	dẽjirf	dẽjer	dẽjerf

Assimilation rules appear in genitives in second declension, with n becoming c when beginning words. Now let's take a look at third declension. Third declension nouns end in -ha, but some end in -e. Both have a vocative of -haj. -ha ending nouns have consistent vocatives, but -e ending nouns have some irregular vocatives. No form uses the base stem except NOMNominative (case)
TRANS subject, INTR argument.SGSingular (number)
one countable entity. No assimilation rules are used outside of stem changes.

	SGSingular (number) one countable entity	DUDual (number) two	PLPlural (number) more than one/few
NOMNominative (case) TRANS subject, INTR argument	base (-ha)	-hap	-he
ACCAccusative (case) TRANS direct object; patient	-hel	-hep	-hẽ
DATDative (case) indirect object; recipient, beneficiary, location	-hajna	-hapa	-hajne
GENGenitive (case) possessive	-hui	-hua	-hue
VOCVocative (case) 'O [addressee]'	base (-haj)	-hajon	-hipl

Now let's see an example with the word rusha:

	SGSingular (number) one countable entity	DUDual (number) two	PLPlural (number) more than one/few
NOMNominative (case) TRANS subject, INTR argument	rusha	rushap	rushe
ACCAccusative (case) TRANS direct object; patient	rushel	rushep	rushẽ
DATDative (case) indirect object; recipient, beneficiary, location	rushajna	rushapa	rushajne
GENGenitive (case) possessive	rushui	rushua	rushue
VOCVocative (case) 'O [addressee]'	rushaj	rushajon	rushipl

TO BE CONTINUED...

Let's look at fourth declension. Compared to the other declensions, there are more irregular stem change rules. The nominative stem might be anything, but the vocative is -oy

	SGSingular (number) one countable entity	DUDual (number) two	PLPlural (number) more than one/few
NOMNominative (case) TRANS subject, INTR argument	base	-out	-ot
ACCAccusative (case) TRANS direct object; patient	-o	-elga	-el
DATDative (case) indirect object; recipient, beneficiary, location	-os	-ov	-ovla
GENGenitive (case) possessive	-õ	-õd	-õt
VOCVocative (case) 'O [addressee]'	base (-uy)	-oyta	-oyge

Let's see it with ķen.

	SGSingular (number) one countable entity	DUDual (number) two	PLPlural (number) more than one/few
NOMNominative (case) TRANS subject, INTR argument	ķen	ķenout	ķenot
ACCAccusative (case) TRANS direct object; patient	ķeno	ķenelga	ķenel
DATDative (case) indirect object; recipient, beneficiary, location	ķenos	ķenov	ķenovla
GENGenitive (case) possessive	ķenõ	ķenõd	ķenõt
VOCVocative (case) 'O [addressee]'	ķenuy	ķenoyta	ķenoyge

All else left to talk about nouns is the adpositions. Various cases are used for dealing with adpositions, which I will mark in the dictionary. Most are prepositions, except when referring to time, in which case they are postpositions.