The basic rule
Unlike English, where red stays red whatever it describes, an Italian adjective agrees with its noun in gender (masculine or feminine) and number (singular or plural). This is true after to be as well. The stem stays; only the ending changes.
Adjectives in -o: four forms
Most adjectives end in -o in their base form. The masculine plural ends in -i, the feminine plural in -e.
Four endings
| Meaning | Masc. sg. | Fem. sg. | Masc. pl. | Fem. pl. |
|---|---|---|---|---|
| red | rosso | rossa | rossi | rosse |
| small | piccolo | piccola | piccoli | piccole |
| new | nuovo | nuova | nuovi | nuove |
| white | bianco | bianca | bianchi | bianche |
With -co, -go, -ca and -ga, an h slips in before the plural ending, just as with nouns, to keep the hard sound: bianco → bianchi, bianca → bianche.
Ho una macchina nuova.
I have a new car.
Il libro rosso è sul tavolo.
The red book is on the table.
I ragazzi sono molto alti.
The boys are very tall.
Le case sono piccole.
The houses are small.
Adjectives in -e: two forms
When the base form ends in -e, there is no separate feminine. These adjectives change for number only: singular in -e, plural in -i, for both genders.
Only two forms
| Meaning | Singular m/f | Plural m/f |
|---|---|---|
| big | grande | grandi |
| green | verde | verdi |
| happy | felice | felici |
| difficult | difficile | difficili |
un libro grande
a big book (m)
una casa grande
a big house (f)
Le ragazze sono felici.
The girls are happy.
Where does the adjective go?
Unlike in English, a descriptive adjective normally comes after the noun. A few short, very common adjectives such as bello, buono, grande or nuovo can also come before it.
il libro rosso
the red book
un film interessante
an interesting film
una macchina veloce
a fast car
Mixed groups
When one adjective describes masculine and feminine nouns together, it takes the masculine plural. A single male in the group is enough.
Marco e Maria sono italiani.
Marco and Maria are Italian.
I ragazzi e le ragazze sono simpatici.
The boys and the girls are nice.
