Third Declension: -is, -ies
The Third Declension
Some -is nouns change like akis, akies, akiai, akį (eye). This is the third declension. Most of these nouns are feminine: graži akis, tamsi naktis.
How It Works
All the forms of akis
- Nominative: akis · plural akys
- Genitive: akies · akių
- Dative: akiai · akims
- Accusative: akį · akis
- Instrumental: akimi · akimis
- Locative: akyje · akyse
- Vocative: akie · akys
The nominative singular and the accusative plural are both akis. The rest of the sentence shows which one you have: in Ji turi mėlynas akis (She has blue eyes), the plural adjective mėlynas shows a plural object.
Sound changes
Before -iai and -ių, t is written č and d is written dž: naktis → nakčiai. A few nouns take -ų in the genitive plural: dantų (of teeth), and naktų beside nakčių (of nights). See I as a Softness Marker.
The masculine few
Dantis, debesis and žvėris have related endings but are masculine, so their adjectives are masculine: baltas dantis, juodas debesis. Their dative singular ends in -iui: dančiui, debesiui. See Two Noun Genders.
Neighbours
For the other kind of -is noun, see The First Declension. The fifth declension shares many of these endings after its extra -en- or -er-; see The Fifth Declension.
Examples (6)
- Ji turi mėlynas akis.
She has blue eyes.
Word by Word: She has blue eyes.
akis here is the accusative plural; the plural adjective mėlynas shows it.
- Iš kokios šalies esate?
What country are you from?
Word by Word: From what country (you) are?
šalis becomes šalies after iš.
- Visą naktį lijo.
It rained all night.
Word by Word: All night rained.
The accusative naktį says how long something lasted.
- Trakų pilis stovi saloje.
Trakai Castle stands on an island.
Word by Word: Of-Trakai castle stands on-island.
pilis is feminine, like most nouns of this group.
- Man skauda dantį.
My tooth hurts.
Word by Word: To-me hurts tooth.
dantis is masculine, but its accusative dantį uses the same ending as akį.
- Ačiū iš visos širdies!
Thank you from the bottom of my heart!
Word by Word: Thanks from all heart!
širdis becomes širdies after iš, and visos agrees in the feminine.
Common Mistakes
Giving a third-declension noun the first-declension genitive.
Iš kokios šalio esate?Iš kokios šalies esate?Šalis is third declension, so its genitive is šalies. Compare first-declension brolis, whose genitive is brolio.
Treating the -is ending as always masculine.
Vakar buvo labai šaltas naktis.Vakar buvo labai šalta naktis.Naktis is feminine, so the adjective is šalta.
Making dantis feminine.
Man skauda priekinę dantį.Man skauda priekinį dantį.Dantis is one of the few masculine nouns here, so the adjective is masculine: priekinį.
How It Connects
Learn This First
The third declension distinguishes nouns such as akis from first-declension nouns in -is.
Related Patterns
- Second Declension: -a, -ėThe Second Declension
The other main feminine pattern.
Level 2 - Fifth Declension: -uo, -ens, -ersThe Fifth Declension
Fifth-declension nouns share many endings with this pattern, after -en- or -er-, but have differences such as genitive vandens.
Level 3 - Two Noun Genders
Most -is nouns here are feminine, a few masculine.
Level 1 - Plural Case Endings
The plural endings akys, akių, akims in context.
Level 2 - The Seven Cases
What each of the seven cases is used for.
Level 1
Words in This Pattern
Practice Third Declension: -is, -ies in Bubblegum
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