If město is the hard neuter, moře ("sea") is its soft twin. It is the model for neuter nouns ending in a soft vowel -e or -ě — with one family carved out: the young-creature kuře type (kuře → kuřete, dítě → dítěte), which slots a -et- in before its endings and so declines quite differently. Everything else in -e / -ě follows moře, and the membership list is full of high-frequency words: pole (field), srdce (heart), slunce (sun), vejce (egg), moře (sea), and the whole family of -iště place nouns like letiště (airport) and hřiště (playground). The pattern is governed by a single rule of thumb: wherever the hard město reaches for a back vowel -o or -u, the soft moře answers with a front vowel -e or -i.
The full moře paradigm
| Case | Singular | Plural |
|---|---|---|
| Nominative (kdo? co?) | moře | moře |
| Genitive (koho? čeho?) | moře | moří |
| Dative (komu? čemu?) | moři | mořím |
| Accusative (koho? co?) | moře (= nom.) | moře (= nom.) |
| Vocative (oslovení) | moře | moře |
| Locative (o kom? o čem?) | (o) moři | (o) mořích |
| Instrumental (kým? čím?) | mořem | moři |
The first thing to register is how much of this table is just the word moře over and over. The bare form covers the nominative, genitive, accusative, and vocative singular and the nominative, accusative, and vocative plural — seven of the fourteen cells. This is the heaviest syncretism of any core paradigm: half the table is a single sound.
Moře bylo ráno úplně klidné, jako zrcadlo.
The sea was perfectly calm in the morning, like a mirror. (moře, nominative singular)
Bydlíme jen kousek od moře, slyšíme ho v noci.
We live just a short way from the sea, we can hear it at night. (od moře, genitive singular — identical to the nominative)
moře against město, cell by cell
The fastest way to own this paradigm is to lay it beside the hard město you already know and watch the back vowel → front vowel swap happen in the same six places every time.
| Case | město (hard) | moře (soft) | The swap |
|---|---|---|---|
| Gen. sg. | města | moře | -a → -e |
| Dat. sg. | městu | moři | -u → -i |
| Loc. sg. | městě | moři | -ě → -i |
| Instr. sg. | městem | mořem | same! |
| Nom./Acc. pl. | města | moře | -a → -e |
| Gen. pl. | měst (zero) | moří | zero → -í |
| Dat. pl. | městům | mořím | -ům → -ím |
| Loc. pl. | městech | mořích | -ech → -ích |
| Instr. pl. | městy | moři | -y → -i |
Only the instrumental singular -em is shared outright. Everywhere else, if you catch yourself wanting město's ending on a soft noun, front it: u becomes i, a becomes e, the bare genitive plural becomes -í.
Každé léto jezdíme k moři na dva týdny.
Every summer we go to the seaside for two weeks. (k moři, dative singular — -i, not the hard -u)
Celé odpoledne jsme se koupali v moři.
We swam in the sea all afternoon. (v moři, locative singular — -i, not -ě/-u)
Slunce se odráželo nad mořem.
The sun was reflecting over the sea. (mořem, instrumental — the one ending it shares with město)
The -í genitive plural
The cell most worth drilling is the genitive plural -í. Where the hard neuter strips to a bare stem (měst, oken), the soft neuter adds -í: moří, polí, srdcí. It surfaces after every quantity word and every number from five up, so it is everyday grammar, not a rarity.
Z letadla byla vidět spousta zelených polí.
From the plane you could see lots of green fields. (pole → polí, genitive plural after spousta)
Vyprávěl o cestě přes sedm moří.
He told of a journey across the seven seas. (moře → moří, genitive plural)
Two everyday members: srdce and slunce
Two of the most common words you'll ever say belong here. srdce (heart) and slunce (sun) decline exactly like moře — v srdci (in the heart), do srdce (into the heart), za sluncem (after the sun).
Mám tě v srdci, ať jsi kdekoli.
I carry you in my heart, wherever you are. (v srdci, locative singular — -i)
Slunce mi svítí přímo do očí.
The sun is shining right into my eyes. (slunce, nominative — the subject)
Otoč se zády ke slunci, ať tě neoslní.
Turn your back to the sun so it doesn't dazzle you. (ke slunci, dative — -i)
Where moře nouns wobble: -iště and vejce
Honesty time — two corners of this paradigm don't behave perfectly, and pretending otherwise would set you up to fail.
The -iště place nouns (letiště, hřiště, parkoviště, sídliště) follow moře in the singular and most of the plural, but their genitive plural is a bare stem in -išť, not -í: hodně letiš*ť*, *pět hřišť*. The collective of place-words simply prefers the zero ending there, the way the hard neuters do.
V okolí Prahy je hned několik letišť.
There are several airports in the vicinity of Prague. (letiště → letišť, genitive plural with the zero ending)
And vejce (egg) has an irregular genitive plural vajec — note the changed vowel — instead of the expected vejcí. There is no rule behind it; it is a frozen oddity you memorise from the shopping list.
Kup, prosím, deset vajec a kostku másla.
Buy ten eggs and a stick of butter, please. (vejce → vajec, an irregular genitive plural)
Common mistakes
❌ Jezdíme každý rok k mořu.
Incorrect — the soft neuter dative is -i, not the hard -u: k moři.
✅ Jezdíme každý rok k moři.
We go to the seaside every year. (k moři)
❌ Koupali jsme se v mořu celý den.
Incorrect — locative of moře is moři; -u belongs to the hard/foreign neuters.
✅ Koupali jsme se v moři celý den.
We swam in the sea all day. (v moři)
❌ Na světě je spousta moř.
Incorrect — the soft genitive plural takes -í, not the hard zero ending: moří.
✅ Na světě je spousta moří.
There are a lot of seas in the world. (moří)
❌ Bydlíme kousek od mořa.
Incorrect — the genitive singular of moře is moře itself (-e), never the hard -a.
✅ Bydlíme kousek od moře.
We live a short way from the sea. (od moře)
❌ Nosím tě ve svém srdcu.
Incorrect — locative of srdce is srdci, not the hard -u.
✅ Nosím tě ve svém srdci.
I carry you in my heart. (ve srdci)
Key takeaways
- moře is the soft neuter model for nouns in -e / -ě: pole, srdce, slunce, vejce, letiště, hřiště.
- It mirrors město with a back-vowel → front-vowel swap: -a → -e, -u → -i, and a -í genitive plural where město has a bare stem. Only the instrumental singular -em is shared.
- Massive syncretism: the bare form moře fills seven of fourteen cells (nom./gen./acc./voc. sg. and nom./acc./voc. pl.).
- Watch two exceptions: -iště nouns take a zero genitive plural (letišť, hřišť), and vejce has the irregular vajec.
Related Topics
- Neuter: The Město ParadigmA2 — The hard neuter pattern město (town/city) — the model for neuter nouns ending in -o, with its full seven-case table, the zero genitive plural, and the fill vowel.
- Neuter: The Kuře Paradigm (animal young, -et-/-at- stems)B1 — Neuters denoting young creatures that expand their stem with -et-/-at- when declined.
- Neuter: The Stavení Paradigm (-í neuters)B1 — The invariable-looking -í neuter declension, including the productive verbal-noun class.
- Neuter Paradigms ComparedB1 — A side-by-side of město, moře, kuře, and stavení to fix the neuter declension system — and a one-line rule for telling them apart.
- How to Read a Declension TableA1 — A practical guide to reading the standard Czech declension table laid out by case and number.