The Indefinite Article: Forms and Uses | Portuguese (Portugal) Grammar

The indefinite article (artigo indefinido) introduces a noun that is new to the conversation or unspecific — the equivalent of English a/an or (in the plural) some. Portuguese has four forms — um, uma, uns, umas — agreeing with the noun in gender and number. The forms are easy; the interesting part is knowing when to use one and when to leave it out, because the English-to-Portuguese mapping is not one-to-one. You will sometimes keep um where English uses a, but at other times Portuguese drops the article in places where English would require one.

This page covers the four forms, the plural uns/umas as a vague quantifier, the contractions with de and em, and the key contexts — especially predicative uses after ser — where Portuguese drops the article that English keeps.

The four forms

	Singular	Plural
Masculine	um	uns
Feminine	uma	umas

Comprei um livro na feira.

I bought a book at the fair.

Tenho uma pergunta para ti.

I have a question for you.

Vi uns amigos no café.

I saw some friends at the café.

Ela trouxe umas flores lindas.

She brought some beautiful flowers.

The singular forms (um, uma) translate English a/an. The plural forms (uns, umas) translate English some — a meaning English often does not express at all.

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English sentences with bare plurals (I bought books, she brought flowers) do not always translate into Portuguese with uns/umas. Bare plurals in Portuguese often stand alone too (comprei livros, trouxe flores). The difference: uns/umas signals a few, some — quantity vague but small; bare plurals signal unspecified quantity, potentially many. Pick uns amigos when you mean "a few friends"; pick bare amigos when you mean "friends" generically.

Contractions with de and em

The indefinite articles optionally contract with de and em to form dum, duma, duns, dumas and num, numa, nuns, numas. In PT-PT, both the contracted and the uncontracted forms are acceptable, and the choice is largely stylistic — uncontracted forms tend to be more common in careful written Portuguese, while contractions are fully standard in speech and informal writing.

Preposition	um	uma	uns	umas
de	dum / de um	duma / de uma	duns / de uns	dumas / de umas
em	num / em um	numa / em uma	nuns / em uns	numas / em umas

Trabalho num banco no centro da cidade.

I work in a bank in the city centre. (em + um = num)

Ela saiu duma empresa grande para montar a própria.

She left a big company to start her own. (de + uma = duma)

Moro numa cidade pequena perto do Porto.

I live in a small town near Porto. (em + uma = numa)

Vim de uma reunião que correu mal.

I just came from a meeting that went badly. (uncontracted is also fine)

Note: unlike the obligatory contractions with the definite article (ao, do, na — always), the indefinite-article contractions are optional. Beginners should be aware that both forms exist and either is acceptable.

Uses of the indefinite article

Introducing a new referent

The primary use is exactly as in English: introducing a noun that has not been established in the conversation.

Havia um homem à porta.

There was a man at the door.

Ontem conheci uma advogada muito interessante.

Yesterday I met a very interesting lawyer.

Eles adotaram um cão há dois meses.

They adopted a dog two months ago.

The first time a referent appears, it is unfamiliar to the listener, so the indefinite article flags it as new. Once introduced, follow-up mentions switch to the definite article or a pronoun:

Comprei um carro. O carro é verde.

I bought a car. The car is green. (second mention — definite)

Vague small quantity — uns, umas

The plural indefinite article marks a small, vague quantity. It is often translated as some, a few, a couple of.

Vou levar uns minutos a explicar isto.

I'm going to take a few minutes to explain this.

Compra umas maçãs no supermercado.

Buy some apples at the supermarket.

Preciso de uns dias para pensar.

I need a few days to think.

Há umas pessoas à porta que querem falar contigo.

There are some people at the door who want to talk to you.

Uns and umas are very common in PT-PT — especially in spoken register, where they soften a statement. Umas horas (a few hours) is softer than horas alone. Uns problemas (some problems) is softer than problemas alone.

Approximation with numbers

A distinctive PT-PT use: uns or umas followed by a number gives an approximate quantity — about, roughly, something like.

Estive lá umas três horas.

I was there about three hours.

Ele deve ter uns quarenta anos.

He must be about forty.

Comprei umas cinco ou seis camisas.

I bought about five or six shirts.

Esperei uns vinte minutos.

I waited about twenty minutes.

Without the uns/umas, the number is exact; with them, approximate. This is a tidy little construction that English awkwardly paraphrases as about, around, roughly.

Identification with a modifier

When ser is followed by a noun that is modified — by an adjective, a relative clause, or another noun phrase — the indefinite article is used.

Ele é um médico excelente.

He's an excellent doctor.

Ela é uma pessoa muito inteligente.

She's a very intelligent person.

É um livro que toda a gente devia ler.

It's a book that everyone should read.

O Porto é uma cidade cheia de charme.

Porto is a city full of charm.

The modifier (excelente, muito inteligente, que toda a gente devia ler, cheia de charme) is what triggers the article. Without the modifier, Portuguese drops it (see below).

Emphasis and exclamatives

The indefinite article signals an emphatic or exclamatory noun — what a...!

Foi uma noite!

What a night!

Tenho uma fome!

I'm so hungry! (literally: I have a hunger!)

Que calor!

What heat! (with que + exclamation)

Tens cá uma paciência!

You have such patience!

This construction — um/uma + noun in an exclamative context — intensifies the noun, turning it into an expressive complaint or wonder. It appears constantly in colloquial PT-PT.

When Portuguese does NOT use the indefinite article

English uses a/an before every singular count noun in most contexts. Portuguese is looser — it drops the article in several predictable situations.

After ser + profession, nationality, religion (unmodified)

The single most important case. When ser is followed by a bare noun of profession, nationality, religion, or political affiliation, Portuguese drops the article.

Sou professor.

I'm a teacher.

Ela é médica.

She's a doctor.

O meu pai é engenheiro.

My father is an engineer.

Somos portugueses.

We're Portuguese.

Ele é católico.

He's Catholic.

Ela é comunista.

She's a communist.

Adding um/uma here (sou um professor) is not grammatical, or at best sounds like an English-transfer mistake.

❌ Sou um professor de português.

Wrong — article unnecessary before unmodified profession.

✅ Sou professor de português.

I'm a Portuguese teacher.

The moment a modifier appears, the article comes back:

Sou um professor de português muito exigente.

I'm a very demanding Portuguese teacher.

Ela é uma médica brilhante.

She's a brilliant doctor.

This contrast — sou médico vs sou um médico excelente — is one of the clearest little rules in Portuguese and one of the first that English speakers internalise.

Generic plurals (bare plurals)

When you make a general statement about a class, Portuguese often uses the bare plural (or the definite article — see definite-articles page) without uns/umas.

Gosto de gatos.

I like cats.

Prefiro cerveja a vinho.

I prefer beer to wine.

Ela escreve poemas.

She writes poems.

Adding uns or umas here (gosto de uns gatos) would shift the meaning to I like some specific small number of cats, which is not what the English sentence means.

Certain prepositional phrases

Fixed expressions of manner, absence, or abstract quality drop the article.

Trabalho sem razão aparente.

I work without apparent reason.

Ela fala com paciência infinita.

She speaks with infinite patience.

Saiu em silêncio.

She left in silence.

Entrou com calma.

He entered with calm.

Once the noun is modified by a definite phrase or relative clause, the article comes back — but unmodified abstract nouns in fixed prepositional constructions drop it.

Some equative como constructions

Ele trabalha como empregado de mesa.

He works as a waiter.

Ela presta serviço como voluntária.

She does voluntary service as a volunteer.

Here, como + bare profession is the PT-PT norm; como um empregado is possible but changes the meaning (more like the way a waiter does).

Comparison with English a/an

Context	English	Portuguese
Introducing new noun	a/an	um / uma
Profession (unmodified)	a/an	— (no article)
Profession (modified)	a/an	um / uma
Generic plural	— (bare plural)	— (bare plural) or os/as
Vague small quantity plural	some, a few	uns / umas
Approximate number	about + number	uns / umas + number
Exclamative	what a! / such!	um! / uma!

The difference to internalise: Portuguese is willing to leave a singular count noun bare (after ser, in fixed expressions), where English would insist on a/an. The moment you see ser + profession or nationality without a modifier, drop the article.

Indefinite article vs definite article — the choice

In many sentences, both articles are grammatical, but they mean different things. The indefinite introduces or classifies; the definite identifies or generalises.

Vi um filme ontem.

I saw a film yesterday. (a film, not yet specified)

Vi o filme ontem.

I saw the film yesterday. (the specific film we've been talking about)

Gosto de um vinho.

I like a (particular, unspecified) wine.

Gosto do vinho.

I like the wine. (the specific wine in front of us, or wine in general — ambiguous)

Gosto de vinho.

I like wine. (generic)

Choosing between these three — um vinho, o vinho, vinho — is one of the subtler skills of Portuguese, and it develops with exposure.

Register notes

(neutral / spoken PT-PT) Uses uns/umas liberally to soften numbers and quantities.
(formal written) Slightly fewer uns/umas approximations; tends toward exact numbers or cerca de / aproximadamente.
(headlines) Articles are dropped in headlines, as in English.
(contracted dum/num) Fully standard in speech. Uncontracted de um/em um is slightly more formal in writing — both acceptable.

Common Mistakes

❌ Eu sou um estudante de engenharia.

Article unnecessary before unmodified profession.

✅ Sou estudante de engenharia.

I'm an engineering student.

❌ Ela é uma portuguesa.

Article unnecessary before unmodified nationality.

✅ Ela é portuguesa.

She's Portuguese.

❌ Gosto de uns gatos.

Changes meaning — should be the bare plural for a generic statement.

✅ Gosto de gatos.

I like cats.

❌ Comprei um pão e um queijo.

Awkward — mass nouns typically take no article, or an appropriate quantifier.

✅ Comprei pão e queijo.

I bought bread and cheese.

❌ Trabalho num um banco.

Doubled determiner — either num or em um, not both.

✅ Trabalho num banco.

I work in a bank.

❌ Esperei cerca de umas duas horas.

Redundant approximation — cerca de already means 'about'.

✅ Esperei umas duas horas.

I waited about two hours.

✅ Esperei cerca de duas horas.

I waited about two hours. (alternative)

Key Takeaways

Portuguese has four indefinite articles: um, uma, uns, umas, agreeing with the noun in gender and number.
Plural uns/umas means some, a few — a small vague quantity.
Uns/umas before a number gives approximation: uns quarenta anos = "about forty years old".
Contractions with de and em (dum, num, duma, numa) are optional — both forms are acceptable in PT-PT.
Drop the article after ser
- unmodified profession, nationality, religion, or political affiliation: sou médico, é portuguesa.
Keep the article after ser
- profession with a modifier: é um médico excelente.
Portuguese bare plurals (gosto de gatos) are the norm for generic statements, not uns/umas.
The indefinite article also appears in exclamatives: foi uma noite! = "what a night!" </content> </invoke>