Regular Adjectives in Italian

Overview

Italian adjectives must agree with the noun they describe in both gender (masculine or feminine) and number (singular or plural). This is one of the most fundamental rules in Italian grammar and something you will use in every sentence that contains a description.

There are two main categories of regular adjectives. Four-form adjectives have a different ending for each combination of gender and number — like "bello, bella, belli, belle" (beautiful). Two-form adjectives have one ending for singular and another for plural, regardless of gender — like "grande, grandi" (big) or "felice, felici" (happy). Once you know which category an adjective belongs to, forming the correct agreement becomes automatic.

This article builds directly on Gender of Nouns. If you are not yet confident with noun gender, review that concept first — you cannot make adjectives agree if you do not know the gender of the noun.

How It Works

Four-Form Adjectives (-o / -a / -i / -e)

These are the most common type. The adjective dictionary form ends in -o (masculine singular).

	Singular	Plural
Masculine	-o (rosso)	-i (rossi)
Feminine	-a (rossa)	-e (rosse)

The adjective changes its ending to match the noun it describes:

• il libro rosso — the red book (m. sg.)
• la casa rossa — the red house (f. sg.)
• i libri rossi — the red books (m. pl.)
• le case rosse — the red houses (f. pl.)

Other common four-form adjectives: alto/a/i/e (tall), piccolo/a/i/e (small), nuovo/a/i/e (new), bianco/a/chi/che (white), lungo/a/ghi/ghe (long).

Two-Form Adjectives (-e / -i)

These adjectives have the same form for both masculine and feminine. They end in -e in the singular and -i in the plural.

	Singular	Plural
Masculine	-e (grande)	-i (grandi)
Feminine	-e (grande)	-i (grandi)

• il libro grande — the big book (m. sg.)
• la casa grande — the big house (f. sg.)
• i libri grandi — the big books (m. pl.)
• le case grandi — the big houses (f. pl.)

Other common two-form adjectives: felice/felici (happy), triste/tristi (sad), interessante/interessanti (interesting), intelligente/intelligenti (intelligent), difficile/difficili (difficult).

Agreement Rules

1. The adjective always matches the noun it modifies in gender and number.
2. With mixed-gender groups, the masculine plural is used: Marco e Giulia sono alti (not alte).
3. With "essere" (to be), the adjective still agrees with the subject: Maria è alta; i ragazzi sono contenti.

Position of Adjectives

Most adjectives come after the noun in Italian — the opposite of English:

• una macchina rossa — a red car
• un film interessante — an interesting film

A small group of very common short adjectives can go before the noun: bello, buono, brutto, grande, piccolo, nuovo, vecchio, giovane. When placed before the noun, they sometimes carry a slightly different or more subjective nuance:

• un grande uomo — a great man (figurative)
• un uomo grande — a big/tall man (physical)

When in doubt at the A1 level, place the adjective after the noun — it is always correct.

Examples in Context

Italian	English	Note
Il gatto è nero.	The cat is black.	Four-form, m. sg.
La borsa è nera.	The bag is black.	Four-form, f. sg.
I gatti sono neri.	The cats are black.	Four-form, m. pl.
Le borse sono nere.	The bags are black.	Four-form, f. pl.
Ho un amico gentile.	I have a kind friend.	Two-form, sg.
Ho due amiche gentili.	I have two kind friends.	Two-form, f. pl.
La pizza è buona.	The pizza is good.	Four-form, f. sg.
I ragazzi sono giovani.	The boys are young.	Two-form, m. pl.
Abbiamo una bella casa.	We have a beautiful house.	Before noun, f. sg.
È un libro difficile.	It is a difficult book.	Two-form, after noun
Le ragazze sono simpatiche.	The girls are nice.	Four-form, f. pl. (-che)
Marco è alto e magro.	Marco is tall and thin.	Two four-form adj., m. sg.
Anna e Marco sono contenti.	Anna and Marco are happy.	Mixed group → m. pl.

Common Mistakes

Forgetting to change the adjective ending

• Wrong: la casa rosso
• Right: la casa rossa
• Why: The noun "casa" is feminine singular, so the adjective must use the feminine singular ending -a, not the masculine -o.

Using feminine plural for mixed-gender groups

• Wrong: Marco e Anna sono alte
• Right: Marco e Anna sono alti
• Why: When a group includes at least one masculine noun or person, the adjective takes the masculine plural form.

Adding gender endings to two-form adjectives

• Wrong: una ragazza intelligenta
• Right: una ragazza intelligente
• Why: "Intelligente" is a two-form adjective. Its singular form is -e for both genders. There is no -a form.

Placing every adjective before the noun

• Wrong: una rossa macchina
• Right: una macchina rossa
• Why: Most adjectives follow the noun in Italian. Only a small group of common short adjectives (bello, buono, grande, piccolo, etc.) regularly appear before the noun.

Forgetting spelling changes with -co/-go adjectives

• Wrong: i libri bianchi → bianci
• Right: i libri bianchi; le scarpe bianche
• Why: Adjectives ending in -co/-go often insert an "h" in the plural to preserve the hard sound: bianco → bianchi/bianche, lungo → lunghi/lunghe.

Practice Tips

1. Drill the four endings as a set. When you learn a new four-form adjective, say all four forms aloud: "rosso, rossa, rossi, rosse." This builds muscle memory so that agreement becomes automatic rather than something you have to think about each time.

2. Sort your vocabulary into two-form vs. four-form. Keep a simple list. When you encounter a new adjective, immediately note whether its base form ends in -o (four-form) or -e (two-form). Knowing the category tells you everything you need about its endings.

3. Practice with real noun-adjective pairs. Rather than studying adjectives in isolation, always pair them with a noun: "il cielo azzurro," "la notte fredda," "un esame difficile." This trains your brain to produce the agreement naturally.

Related Concepts

• Prerequisite: Gender of Nouns — you must know a noun's gender to choose the correct adjective ending
• Next step: Bello & Buono — these adjectives have special forms when placed before a noun
• Next step: Demonstratives — questo/quello follow similar agreement patterns
• Next step: Adjective Position — deeper rules for when adjectives go before or after the noun
• Next step: Indefinite Adjectives — ogni, qualche, alcuni and their agreement rules
• Next step: Comparatives — più alto, meno difficile — comparing with adjectives
• Next step: Adverbs of Manner — turning adjectives into adverbs with -mente