Common Mistakes: Numbers and Noun Case

English keeps numbers beautifully inert: "one house, two houses, five houses, twenty houses" — the noun is a plain plural from two onward, and the verb agrees with it as a plural every time. Czech does almost the opposite. The number reaches into the noun and reshapes its case, and above four it even shrinks the verb to a neuter singular. There are three tiers — one, two-to-four, and five-plus — each with its own noun form, and English speakers who import the flat English pattern make the single most reliable intermediate error in the language: pět studenti přišli instead of pět studentů přišlo. This page lays out the three tiers, the verb rule, and the compound-number twist.

The three tiers

Everything comes down to which tier the number falls into. Memorize the boundaries: 1 alone, 2–4, and 5 and up.

The jump from four to five is the shock: the noun leaps into the genitive plural and the verb collapses to a neuter singular. Let us take the tiers one at a time.

Tier 1: jeden + singular

After jeden (masc.), jedna (fem.), jedno (neut.), the noun is a plain nominative singular, and jeden agrees with the noun's gender — exactly as an adjective would. The verb is singular.

Tier 2: dva/tři/čtyři + nominative plural

After dva/dvě, tři, čtyři, the noun is a nominative plural and the verb is plural — this is the one tier that behaves like English, which is precisely why learners then wrongly extend it to five and beyond.

Note that dva has a gender form: dva for masculine, dvě for feminine and neuter (dva domy but dvě ženy, dvě okna). That gender split is a separate common trap; here just hold onto the case: nominative plural across 2–4.

Tier 3: pět+ → genitive plural + neuter-singular verb

From pět ("five") upward — pět, šest, sedm, osm, devět, deset, dvacet, sto, tisíc — two things happen at once, and both defy English intuition:

1. The noun jumps to the genitive plural. pět domů, deset žen, dvacet studentů.
2. The verb goes 3rd-person singular neuter. In the past that means the neuter -lo ending, even when you are obviously talking about many people or things.

The reason the noun is genitive is historical: numbers from five up were once quantity-nouns that governed a genitive, exactly like English "a dozen of eggs" or "a lot of people." The vanished of is why the noun stays genitive plural, and because the number was itself a singular noun, the whole phrase counts as one neuter thing — hence the singular neuter verb. The full logic and the genitive-plural forms are on Cardinal Numbers 5 and Up.

The side-by-side that locks it in

The clearest drill is to put 2–4 and 5+ back to back and watch both the noun case and the verb flip as you cross from four to five.

Say the pair out loud: přišli (plural) versus přišlo (singular neuter). That grammatical "click" is the whole lesson. The English speaker's error is to keep přišli — the plural verb — for both, because English keeps the verb plural throughout.

The compound twist: the LAST word decides

For compound numbers — dvacet jedna, sto dvacet tři, sto padesát pět — only the final element controls the noun. Strip away everything but the last word and apply its tier:

• ends in 1 → singular (prescriptively) or the colloquial frozen genitive plural
• ends in 2/3/4 → nominative plural
• ends in 5–9 or 0 → genitive plural

The "...1" case is genuinely fiddly. Prescriptively, jeden agrees and the noun is singular: dvacet jedna koruna (21 crowns). But in real speech almost everyone freezes the number and uses the genitive plural: dvacet jedna korun. Both are understood; the frozen genitive plural is what you will actually hear.

The details are on compound cardinal numbers.

One boundary: this is the subject/object pattern only

The genitive-plural-plus-singular-verb behaviour holds only when the counted phrase is the subject or direct object (nominative or accusative). The moment the phrase falls under a preposition or into another case, the numeral itself starts declining and the noun simply matches it — the "frozen genitive" melts.

That oblique behaviour has its own page, case propagation through number phrases. For everyday subject/object counting, hold onto the three-tier rule.

Common Mistakes

The commonest form error: reaching for the singular after 5+. It must be the genitive plural.

The signature intermediate mistake: importing the English plural noun and plural verb. Both must change after 5+.

Tier 2 needs the plural noun (and plural verb), not the bare singular.

The neuter-singular verb belongs to 5+, not to 2–4. Don't over-apply it downward.

In compounds, the last word rules: ...5 → genitive plural.

Key Takeaways

• Three tiers: 1 → nominative singular + singular verb (jeden dům stojí); 2–4 → nominative plural + plural verb (dva domy stojí); 5+ → genitive plural + neuter-singular verb (pět domů stojí, Přišlo pět studentů).
• The 5+ tier is the killer: both the noun (→ gen. pl.) and the verb (→ 3sg neuter, past -lo) change. Do not import the flat English plural.
• Compounds are decided by the last element: dvacet dvě koruny, dvacet pět korun, colloquial dvacet jedna korun.
• The pattern applies only in the nominative/accusative; in oblique cases the number and noun both inflect (o pěti studentech).
• Historical mnemonic: 5+ means "a dozen of…" — the "of" gives you the genitive, the singular "a dozen" gives you the singular verb.