In short

A Portuguese adjective must agree with its noun in gender and number, so it changes shape the way nouns did in noun gender and number: um carro branco, uma casa branca, uns carros brancos, umas casas brancas. It also usually sits after the noun, the opposite of English - a red apple is uma maçã vermelha. A small group of common adjectives can move in front, and a handful actually change meaning depending on which side they land.

The rule

Agreement in gender and number

The adjective copies the gender and number of the noun it describes. How many forms it has depends on its ending:

• Adjectives in -o have all four forms: alto, alta, altos, altas.
• Adjectives in -e or in most consonants do not change for gender - only for number: grande / grandes, feliz / felizes, azul / azuis. So um homem inteligente and uma mulher inteligente share one form.
• Adjectives in -or usually add -a for the feminine: trabalhador / trabalhadora, falador / faladora.
• Nationality adjectives ending in a consonant DO inflect: português / portuguesa, inglês / inglesa, espanhol / espanhola. Note that nationalities and languages are written lower-case: ela é francesa, falo português.

Plurals follow the same rules as nouns (see noun gender and number): add -s after a vowel (bonito -> bonitos), -es after -r or -z (maior -> maiores, feliz -> felizes), and -is for words in -l (azul -> azuis, fácil -> fáceis). Adjectives in -ão do not all behave alike: the nationality type takes -ã in the feminine and keeps its noun plural (alemão -> alemã, alemães, alemãs), while the everyday character adjectives take -ona / -ões / -onas (brincalhão -> brincalhona, brincalhões, brincalhonas; likewise chorão, comilão).

Agreement with more than one noun

When one adjective describes two or more nouns, it goes plural, and if the nouns are of mixed gender the masculine wins:

• o pai e a mãe estão cansados - “the father and mother are tired” (masculine plural cansados).
• uma saia e um casaco novos - “a new skirt and coat” (masculine plural novos).

Where the adjective goes: after the noun

The default and by far the commonest position is after the noun: um livro interessante, uma cidade bonita, sapatos pretos. Reaching for the English order and saying uma vermelha maçã is the single most audible beginner error.

A few short, very common adjectives naturally come before the noun, especially bom, mau, grande, pequeno and ordinals: um bom livro, um mau dia, o primeiro comboio. Putting them before tends to read as a general or subjective judgement rather than a distinguishing feature.

Adjectives that change meaning by position

For a small set, the position is not a matter of taste - it changes the meaning. Learn these as pairs:

• um grande homem “a great man” vs um homem grande “a big/tall man”.
• um velho amigo “an old (long-standing) friend” vs um amigo velho “an elderly friend”.
• um pobre homem “a poor (pitiable) man” vs um homem pobre “a poor (penniless) man”.
• uma simples pergunta “a mere question” vs uma pergunta simples “a simple (easy) question”.

Before the noun the adjective is figurative or emotional; after it, literal and descriptive.

Forms & patterns

Adjective classes and their four (or two) forms:

Position and meaning:

Examples

Common mistakes

• uma vermelha maçã -> uma maçã vermelha - the adjective normally goes AFTER the noun; do not import the English word order.
• a casa branco / meninas altos -> a casa branca, meninas altas - the adjective must copy the noun’s gender and number, every time.
• uma mulher grande meaning “a great woman” -> uma grande mulher - after the noun grande means “big”; the “great” sense needs the pre-noun slot.
• granda, inteligenta -> grande, inteligente - adjectives in -e have no separate feminine; only nationalities and -or words add -a (portuguesa, trabalhadora).
• sapatos azuls / problemas fáceis written facils -> azuis, fáceis - adjectives in -l drop it and add -is.
• Ela é Francesa -> Ela é francesa - nationalities and language names are lower-case in Portuguese.
• o pai e a mãe estão cansadas -> cansados - with mixed-gender nouns the shared adjective takes the masculine plural.

Tips

• Make “noun first, adjective second” your reflex: comida boa, tempo bom, uma pergunta difícil. Only bom, mau, grande, pequeno and ordinals slip comfortably in front.
• Tie the adjective’s ending to the noun you can see: if the noun is feminine plural, the adjective ends the same way (as casas antigas).
• Keep the meaning-shift pairs on a flashcard - grande, velho, pobre, simples - because getting the side wrong changes what you actually say.
• For nationalities remember two things at once: they inflect for gender (espanhol / espanhola) and they are written lower-case.
• When two nouns share one adjective, default to masculine plural unless both nouns are feminine.
• In Brazil: agreement and position work exactly as in Portugal; the differences you notice are vocabulary, not grammar - Portugal’s giro / gira (“nice, cool”) is Brazil’s legal, but both still agree with their noun.