An English adjective is inert. Big is big whether it describes a garden, a house, or fifty gardens, and whether that garden is a subject, an object or a possessor. A Greek adjective is the opposite: it takes on the gender, number and case of the noun it belongs to, and it changes shape every time any of those three changes. Getting that copy right, automatically, every time, is the single skill this page is about. It is not hard to understand — it is hard to make reflexive.
Agreement is copying three things
When you attach an adjective to a noun, you read three properties off the noun and stamp them onto the adjective:
- Gender — is the noun masculine, feminine or neuter?
- Number — is it singular or plural?
- Case — what job is the noun doing (subject, object, possessor, address)?
The adjective is not a fixed word you drop in front; it is a word you rebuild to match. Take μεγάλος ("big") and change one property at a time.
Changing the gender
Same adjective, three genders, three endings:
| Gender | Phrase | Meaning |
|---|---|---|
| Masculine | ο μεγάλος κήπος | the big garden |
| Feminine | η μεγάλη αυλή | the big yard |
| Neuter | το μεγάλο δωμάτιο | the big room |
Έχουν έναν μεγάλο κήπο με λεμονιές κι έναν μικρό λαχανόκηπο.
échun énan meghálo kípo me lemoniés ke énan mikró lachanókipo
They've got a big garden with lemon trees and a small vegetable patch.
Μείναμε σε ένα μεγάλο δωμάτιο με θέα στη θάλασσα.
míname se éna meghálo dhomátio me théa sti thálasa
We stayed in a big room looking out over the sea.
Changing the number
Singular to plural, again one adjective, three genders:
| Masculine | Feminine | Neuter | |
|---|---|---|---|
| Singular | μεγάλος | μεγάλη | μεγάλο |
| Plural | μεγάλοι | μεγάλες | μεγάλα |
Οι μεγάλοι κήποι θέλουν πότισμα κάθε μέρα το καλοκαίρι.
i megháli kípi thélun pótizma káthe méra to kalokéri
Big gardens need watering every day in the summer.
Τα παιδιά έχουν γίνει μεγάλα, δεν τα αναγνωρίζω.
ta pedhiá échun yíni meghála, dhen ta anaghnorízo
The kids have got so big, I hardly recognise them.
Watch the neuter plural: μεγάλα. Neuter plural adjectives always end in -α, and this trips English speakers up because so many everyday things — παιδιά (children), σπίτια (houses), αυτοκίνητα (cars), βιβλία (books) — are neuter.
Changing the case
This is the dimension English has no memory of. As the noun phrase moves from subject to possessor to object, the adjective moves with it. Here is ο μεγάλος κήπος through the singular cases:
| Case | Phrase | Role in the sentence |
|---|---|---|
| Nominative | ο μεγάλος κήπος | the big garden (subject) |
| Genitive | του μεγάλου κήπου | of the big garden (possessor) |
| Accusative | τον μεγάλο κήπο | the big garden (object) |
Ο μεγάλος κήπος του παππού είναι η αδυναμία μου.
o meghálos kípos tu papú íne i adhinamía mu
Grandpa's big garden is my weak spot.
Η συντήρηση του μεγάλου κήπου κοστίζει μια περιουσία.
i sindírisi tu meghálu kípu kostízi mia periusía
The upkeep of the big garden costs a fortune.
Ποτίζω τον μεγάλο κήπο κάθε βράδυ πριν σκοτεινιάσει.
potízo ton meghálo kípo káthe vrádhi prin skotiniási
I water the big garden every evening before it gets dark.
The whole grid — all four cases in both numbers, and how it interacts with the article — is on adjectives in -ος / -η / -ο. What matters here is the principle: the adjective takes the same case as its noun, whatever that case is. It is never a fixed dictionary form.
Two positions, one rule
An adjective agrees no matter where it sits, but there are two places it can sit.
Attributive — inside the noun phrase, between the article and the noun: ο μεγάλος κήπος. Here it copies whatever case the phrase is in, as you just saw.
Predicative — after a linking verb like είμαι (to be), γίνομαι (to become), φαίνομαι (to seem), μένω (to stay). Here the adjective describes the subject across the verb, and it agrees with that subject — which is in the nominative.
Το σπίτι τους είναι πολύ μεγάλο για τρεις ανθρώπους.
to spíti tus íne polí meghálo ya tris anthrópus
Their house is much too big for three people.
Η σούπα έμεινε κρύα όσο περιμέναμε.
i súpa émine kría óso periméname
The soup went cold while we waited.
Τα παιδιά ήταν κουρασμένα και νυσταγμένα μετά την εκδρομή.
ta pedhiá ítan kurazména ke nistaghména metá tin ekdhromí
The kids were tired and sleepy after the trip.
In all three the adjective agrees with the subject in gender and number and stands in the nominative: μεγάλο matches neuter σπίτι, κρύα matches feminine σούπα, κουρασμένα matches neuter plural παιδιά. The dedicated treatment of this slot — which verbs take it, and the difference from a true attributive — is on predicative adjectives.
How this splits from "case agreement"
You will also meet agreement on the case agreement within the noun phrase page, and it is worth being clear about who owns what. That page is about the whole noun phrase moving as one block — article, adjective(s), determiner and noun all carrying the same case, so that you decline the phrase as a unit rather than word by word. This page is about the adjective specifically: how it forms its own endings, and the fact that it agrees in the predicative position too, which the noun phrase page does not cover. If you want the phrase-as-a-unit reflex, read that page; if you want the adjective's forms, stay here and go on to the paradigm.
Common Mistakes
1. Leaving the adjective in its masculine dictionary form. The commonest error of all — the adjective must match the noun's gender.
❌ Η γιαγιά μου μαγειρεύει πολύ νόστιμο φαγητό, ήταν μεγάλο μάγειρας.
Incorrect — μάγειρας is masculine but here we need the feminine: μεγάλη μαγείρισσα.
✅ Η γιαγιά μου ήταν μεγάλη μαγείρισσα, μαγείρευε για όλη τη γειτονιά.
i yayá mu ítan megháli mayírisa, mayíreve ya óli ti yitoniá
My grandmother was a great cook — she cooked for the whole neighbourhood.
2. Agreeing in gender but forgetting the case. The phrase is an object here, so the adjective must go accusative, not stay nominative.
❌ Θέλω να νοικιάσω ένα σπίτι με μεγάλος κήπο.
Incorrect — the adjective is accusative like its noun: μεγάλο κήπο.
✅ Θέλω να νοικιάσω ένα σπίτι με μεγάλο κήπο.
thélo na nikiáso éna spíti me meghálo kípo
I want to rent a house with a big garden.
3. Not agreeing in the predicative position. After είμαι the adjective still matches the subject's gender.
❌ Η καινούρια δουλειά είναι πολύ κουρασμένο.
Incorrect — δουλειά is feminine: είναι πολύ κουραστική.
✅ Η καινούρια δουλειά είναι πολύ κουραστική, γυρίζω ψόφια.
i kenúria dhuliá íne polí kurastikí, yirízo psófia
The new job is really exhausting — I come home wrecked.
4. Giving a neuter plural noun a masculine or feminine adjective. Neuter plurals take -α.
❌ Μου αρέσουν τα ελληνικά νησιά, είναι πραγματικά όμορφοι.
Incorrect — νησιά is neuter plural: είναι πραγματικά όμορφα.
✅ Μου αρέσουν τα ελληνικά νησιά, είναι πραγματικά όμορφα.
mu arésun ta eliniká nisiá, íne praghmatiká ómorfa
I love the Greek islands — they're genuinely beautiful.
5. Changing the noun's case but leaving the adjective behind. In a genitive phrase everything goes genitive together.
❌ Το χρώμα του μεγάλο δωματίου δεν μου αρέσει.
Incorrect — the adjective is genitive too: του μεγάλου δωματίου.
✅ Το χρώμα του μεγάλου δωματίου δεν μου αρέσει καθόλου.
to chróma tu meghálu dhomatíu dhen mu arési kathólu
I don't like the colour of the big room at all.
Key Takeaways
- Agreement is copying three properties — gender, number, case — from the noun onto the adjective, every time.
- The adjective takes the same case as its noun: ο μεγάλος κήπος → του μεγάλου κήπου → τον μεγάλο κήπο. It is never a fixed dictionary form.
- Neuter plural adjectives end in -α (μεγάλα παιδιά), which is easy to forget because so many objects are neuter.
- Agreement holds in both positions: attributive (ο μεγάλος κήπος, copying the phrase's case) and predicative (το σπίτι είναι μεγάλο, nominative, matching the subject).
- The case agreement page owns the whole phrase as a unit; this page owns the adjective's own forms and its predicative behaviour.
- Build the phrase as a block: pick the case once, read gender and number off the noun, and apply the triple to the article and every adjective at the same time.
Now practice Greek
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Start learning Greek →Related Topics
- Adjectives in -ος / -η / -οA1 — The full paradigm of the largest and most regular Greek adjective class — καλός, μικρός, ψηλός, όμορφος — declined across all four cases, both numbers and all three genders, with the useful shortcut that each gender copies a noun declension you already know, plus the vocative -ε and why these adjectives keep their accent fixed where the matching nouns shift it.
- Case Agreement Within the Noun PhraseA2 — Why Greek inflects three or four words where English inflects none — ο καλός άνθρωπος → του καλού ανθρώπου → τον καλό άνθρωπο — how to decline a whole phrase as one unit, why the endings need not look alike, and what this concord buys you in word-order freedom.
- Predicative AdjectivesA2 — The adjective after a linking verb — Ο καφές είναι κρύος, Η σούπα είναι κρύα, Τα παιδιά είναι κουρασμένα — where it drops the article, takes the nominative and agrees in gender and number with the subject, plus the object-predicate twist (Τη βρήκα αλλαγμένη) that agrees with an accusative instead.