Adjective Agreement

Adjective agreement is a fundamental rule in Italian. Unlike English, where adjectives are invariable, most Italian adjectives must reflect the characteristics of the noun they modify.

1. Class 1 Adjectives (-o/-a/-i/-e)
These have four distinct forms:

• Masculine Singular: -o (un libro rosso - a red book)
• Feminine Singular: -a (una penna rossa - a red pen)
• Masculine Plural: -i (due libri rossi - two red books)
• Feminine Plural: -e (due penne rosse - two red pens)

Spelling Notes for Class 1:

• Feminine adjectives ending in -ca and -ga always add an h in the plural (-che, -ghe) to keep the hard sound (e.g., lunga → lunghe - long). Masculine adjectives in -co and -go usually become -chi and -ghi if the stress is on the second-to-last syllable (e.g., stanco → stanchi - tired), but become -ci and -gi if the stress is on the third-to-last syllable (e.g., simpatico → simpatici - nice). Note: There are common exceptions to both rules. For example, amico (friend) → amici, nemico (enemy) → nemici, and greco (Greek) → greci change to a soft sound despite penultimate stress, while carico (loaded) → carichi and analogo (analogous) → analoghi keep the hard sound despite antepenultimate stress.
• Adjectives ending in an unstressed -io merge the plural -i ending with the unstressed -i of the stem, resulting in a single -i (e.g., vecchio → vecchi - old). However, if the -i- is stressed, both i's are kept in the plural (e.g., restìo → restìi - reluctant, pìo → pìi - pious).

2. Class 2 Adjectives (-e/-i)
These have only two forms and are the same for both genders in the singular:

• Singular (M/F): -e (un ragazzo/una ragazza intelligente - an intelligent boy/girl, un libro arancione - an orange book)
• Plural (M/F): -i (ragazzi/ragazze intelligenti - intelligent boys/girls, libri arancioni - orange books)

3. Adjectives ending in -a in the singular
These adjectives (often describing professions, beliefs, or traits, such as those ending in -ista) have three forms:

• Singular (M/F): -a (un turista/una turista ottimista - an optimistic tourist, ipocrita - hypocritical, entusiasta - enthusiastic)
• Masculine Plural: -i (due turisti ottimisti - two optimistic tourists, ipocriti - hypocritical)
• Feminine Plural: -e (due turiste ottimiste - two optimistic tourists, ipocrite - hypocritical)

4. Invariable Adjectives
Some adjectives never change. This includes foreign loanwords (chic, snob), colors derived from nouns (rosa - pink, viola - purple), and monosyllabic or accented words (blu - blue, indù - Hindu). Additionally, compound colors (e.g., verde scuro - dark green, rosso mattone - brick red) are invariable. Note: while arancione changes to arancioni, the noun-color arancio is invariable.

5. Mixed Gender Agreement
When an adjective modifies multiple nouns of different genders, it defaults to the masculine plural form (e.g., Il ragazzo e la ragazza sono simpatici. - The boy and the girl are nice.).

6. Shortened Forms of bello and buono
When placed before a noun, the adjectives bello (beautiful) and buono (good) have special irregular agreement rules. Bello mimics the forms of the definite articles (e.g., un bel libro - a beautiful book, un bell'albero - a beautiful tree, dei bei libri - some beautiful books), while buono mimics the forms of the indefinite articles (e.g., un buon libro - a good book, un buon amico - a good friend).