A Czech adjective lives in one of two positions, and the position decides which case it takes. Attributive adjectives stand next to the noun they describe (almost always before it) and copy the noun's full case: nový dům, v novém domě, se starou knihou. Predicative adjectives stand apart from the subject, on the other side of a linking verb like být (to be), and they default to the nominative: Dům je nový. The adjective root is identical in both roles — only the case driven by its grammatical job changes. Get this distinction right and a whole category of mistakes disappears.
Attributive: takes the noun's case
An attributive adjective is welded to its noun and shares its gender, number, and case. When the noun phrase goes into the locative, the genitive, or the instrumental, the adjective goes there too. This is the behaviour drilled on the hard adjective page.
Bydlíme v novém domě hned u parku.
We live in a new house right by the park. (locative — both words inflect)
Včera jsem se potkal se starou kamarádkou ze školy.
Yesterday I ran into an old friend from school. (instrumental — starou kamarádkou)
Koupili jsme malý kulatý stůl do kuchyně.
We bought a small round table for the kitchen. (accusative — malý kulatý stůl)
In every one of these, the adjective is inside the noun phrase, so it wears whatever case the phrase wears.
Predicative: stands in the nominative
When the adjective is separated from the subject by a linking verb — most often být (to be), but also zůstat (to stay), zdát se (to seem) — it describes the subject from a distance. It agrees with the subject in gender and number, but the case is the nominative, because the subject itself is nominative.
Ten dům je úplně nový, postavili ho loni.
That house is brand new, they built it last year. (predicative nominative — nový)
Ta kniha je dost stará, ale pořád zajímavá.
That book is quite old, but still interesting. (feminine — stará, zajímavá)
Děti jsou po výletě hrozně unavené.
The children are terribly tired after the trip. (feminine plural — unavené)
This is exactly where English speakers stumble, because in English the predicate adjective looks the same as the attributive one (a new house / the house is new). In Czech the gender-and-number agreement still applies in the predicate — Ta polévka je horká (feminine), Ty knihy jsou staré (plural) — but the case stays firmly nominative.
The same adjective, both ways
Watch one adjective switch roles. Attributive, it bends to the noun's oblique case; predicative, it snaps back to the nominative:
Celý víkend se starám o nemocného otce.
I'm looking after my sick father all weekend. (attributive accusative — nemocného otce)
Otec je nemocný, leží v posteli s horečkou.
Dad is sick, he's lying in bed with a fever. (predicative nominative — nemocný)
Same word, nemocný → nemocného → nemocný: the only thing that moved is the case demanded by the adjective's position.
The exception: stát se takes the instrumental
One frequent verb breaks the nominative default. After stát se (to become), the predicate noun or adjective normally goes into the instrumental, expressing transition into a new state. This is the same instrumental-predicate logic that governs být in some formal uses; see instrumental predicate.
Po pár letech se stal slavným.
After a few years he became famous. (instrumental — slavným)
Chce se stát lékařem jako jeho táta.
He wants to become a doctor like his dad. (predicate noun in the instrumental — lékařem)
The verb zdát se (to seem) and zůstat (to remain) accept either case — the nominative is everyday and neutral, the instrumental sounds a touch more formal: Zdál se mi nudný / Zdál se mi nudným (both: He seemed boring to me).
There is a clean logic uniting these two patterns, and seeing it spares you from memorising verb by verb. Být works like an equals sign: it states that the subject is the property, so both sides sit in the same case — the nominative. Stát se does not equate; it describes movement into a new state, and Czech reserves the instrumental for exactly that sense of passing through or ending up as something (the same instrumental you meet in jet vlakem, to travel by train). So je slavný says "he is famous," a static identity in the nominative, while stal se slavným says "he turned into a famous person," a transition in the instrumental. The case is not an arbitrary rule attached to the verb — it mirrors the meaning of the verb itself.
A note on short-form predicatives
A tiny set of adjectives keep an old short form that appears only in the predicate — most importantly rád (glad), which has no long attributive form at all in this meaning:
Jsem rád, že jsi konečně dorazil.
I'm glad you finally arrived. (short-form predicative — rád)
Rád agrees in gender and number (ráda for a woman, rádi for a group) but never takes a case other than this fixed nominative shape. These are collected on the short forms page.
Common Mistakes
❌ Ten dům je novém.
Incorrect — a predicative adjective after být is nominative, not locative: je nový.
✅ Ten dům je nový.
That house is new.
❌ Bydlím v nový dům.
Incorrect — an attributive adjective must take the noun's case: v novém domě.
✅ Bydlím v novém domě.
I live in a new house.
❌ Časem se stal slavný.
Incorrect — stát se takes the instrumental: stal se slavným.
✅ Časem se stal slavným.
Over time he became famous.
❌ Ta polévka je horkou.
Incorrect — over-applying the instrumental; after být the predicate is nominative: je horká.
✅ Ta polévka je horká.
The soup is hot.
❌ Ty knihy jsou starý.
Incorrect — the predicative adjective still agrees in number: a plural subject needs staré.
✅ Ty knihy jsou staré.
Those books are old.
Key Takeaways
- Attributive (before the noun) → the adjective copies the noun's full case: v novém domě, se starou knihou.
- Predicative (after být, zůstat, zdát se) → the adjective is nominative, agreeing only in gender and number: Dům je nový.
- After stát se (to become), the predicate goes into the instrumental: stal se slavným, lékařem.
- Predicative agreement in gender and number is still obligatory: je horká, jsou staré.
- A few short-form predicatives like rád exist only after a linking verb.
Now practice Czech
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Start learning Czech→Related Topics
- Hard Adjectives: the -ý/-á/-é PatternA2 — The largest Czech adjective class — model mladý — agrees with its noun in gender, number, and case, with the long vowels -ého, -ému, -ým as its signature.
- Short-Form Adjectives: rád, zdráv, hodenB1 — The small surviving set of short-form (nominal) adjectives that appear only as predicates — rád above all, plus zdráv, hoden, jist and the past-passive participles — and why they never stand before a noun.
- Predicate Nominative with BýtA2 — Why the complement of the verb 'to be' usually stands in the nominative, and when the instrumental competes.
- The Instrumental as Predicate (stal se učitelem)B1 — Why professions, roles, and changed states after být and stát se take the instrumental.
- Order of Multiple AdjectivesB1 — How several adjectives line up before a noun and where commas go.