Adjective Number Agreement

Just as Italian adjectives must agree in gender, they must also agree in number — singular or plural. This lesson focuses on the plural forms of adjectives, including the regular patterns and the important spelling rules that apply to certain consonant endings.

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Regular Plural Formation

The regular rules for making adjectives plural are straightforward:

Singular Ending	Plural Ending	Example
-o (masc.)	-i	rosso → rossi
-a (fem.)	-e	rossa → rosse
-e (masc. or fem.)	-i	grande → grandi

il gatto nero     →  i gatti neri      (the black cats, masc.)
la gonna nera     →  le gonne nere     (the black skirts, fem.)
il ponte grande   →  i ponti grandi    (the big bridges, masc.)
la città grande   →  le città grandi   (the big cities, fem.)

Tip: The plural rules for adjectives mirror the plural rules for nouns. Learn one set and you learn both.

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Adjectives Ending in -co and -go (Masculine)

Masculine adjectives ending in -co and -go require a spelling change in the plural to preserve the hard "k" or "g" sound. An h is inserted before the -i ending.

The -co → -chi / -ci Rule

Pattern	When	Examples
-co → -chi	Most adjectives (especially if stress falls on the second-to-last syllable)	bianco → bianchi, stanco → stanchi, ricco → ricchi, fresco → freschi, antico → antichi, sporco → sporchi
-co → -ci	Some adjectives (especially if stress falls on the third-to-last syllable)	simpatico → simpatici, antipatico → antipatici, magnifico → magnifici, pratico → pratici

i muri bianchi       (the white walls)
i ragazzi stanchi    (the tired boys)
i monumenti antichi  (the ancient monuments)

BUT:
i ragazzi simpatici  (the likeable boys)
i risultati pratici  (the practical results)

Tip: The stress pattern is a useful guide. Words stressed on the penultimate (second-to-last) syllable usually take -chi (bianco → bianchi). Words stressed on the antepenultimate (third-to-last) syllable usually take -ci (simpatico → simpatici). However, there are exceptions, so it is best to learn common words individually.

The -go → -ghi Rule

Adjectives ending in -go almost always become -ghi in the masculine plural:

Singular	Plural	Meaning
largo	larghi	wide
lungo	lunghi	long
vago	vaghi	vague
analogo	analoghi	analogous

i fiumi larghi    (the wide rivers)
i viaggi lunghi   (the long journeys)

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Adjectives Ending in -ca and -ga (Feminine)

Feminine adjectives ending in -ca and -ga always add h before the -e plural ending to maintain the hard sound:

Singular	Plural	Meaning
bianca	bianche	white
stanca	stanche	tired
ricca	ricche	rich
larga	larghe	wide
lunga	lunghe	long
simpatica	simpatiche	likeable
antica	antiche	ancient

le case bianche      (the white houses)
le strade larghe     (the wide streets)
le ragazze simpatiche (the likeable girls)

Tip: The feminine plural is more consistent than the masculine — -ca always becomes -che and -ga always becomes -ghe. No exceptions.

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Adjectives Ending in -io

When a masculine adjective ends in -io, the plural depends on whether the i is stressed: