Começar a + Infinitive (Start Doing) | Portuguese (Portugal) Grammar

To mark the beginning of an action — the exact moment when something that was not happening starts happening — European Portuguese uses começar a + infinitive. Começo a perceber means "I'm starting to understand"; começou a chover means "it started to rain." This inchoative periphrasis is one of the building blocks of A2 conversation: it lets you zoom in on the threshold between not doing something and doing it. This page gives the full paradigm, handles the two tricky spelling shifts (ç ↔ c, and the acute accent on nós preterite), and contrasts começar a with pôr-se a (abrupt start) and passar a (switch to).

The three slots

Slot	What fills it	What changes
auxiliary	começar, in some tense	conjugates for person, number, tense
linker	a (plain preposition)	never changes
main verb	bare infinitive	never changes form

Começo a pensar que tens razão.

I'm starting to think you're right.

A criança começou a chorar quando a mãe saiu.

The child started crying when her mother left.

Paradigm across the key tenses

Começar is a regular -ar verb with two orthographic habits: the ç of the stem switches to plain c before the vowel e (to preserve the soft sound), and the nós preterite takes an acute accent.

Present — "I am starting"

Subject	começar (present)	Example with falar
eu	começo	começo a falar
tu	começas	começas a falar
ele / ela / você	começa	começa a falar
nós	começamos	começamos a falar
eles / elas / vocês	começam	começam a falar

The ç stays throughout the present because every ending starts with a back vowel (-o, -as, -a, -amos, -am). The ç only yields to plain c before e or i.

Estás a ver? Já começo a perceber como funciona.

See? I'm starting to understand how it works.

Os dias começam a ficar mais curtos.

The days are starting to get shorter.

Preterite — "started, began"

This is where the spelling gets interesting. Because the eu preterite ending is -ei (a front vowel), the stem ç switches to plain c: comecei, not começei. Everywhere else the ç is preserved.

Subject	começar (preterite)	Example with trabalhar
eu	comecei	comecei a trabalhar
tu	começaste	começaste a trabalhar
ele / ela / você	começou	começou a trabalhar
nós	começámos	começámos a trabalhar
eles / elas / vocês	começaram	começaram a trabalhar

💡

Two spelling watches in the preterite: (1) the eu form is comecei (plain c, because the ending -ei begins with a front vowel), and (2) the nós form is começámos (acute accent on the á) to distinguish the preterite from the present começamos. Native speakers also routinely miss the second one — but in careful EP writing, both are mandatory.

Comecei a aprender português há dois anos.

I started learning Portuguese two years ago.

Começou a nevar ao princípio da tarde.

It started snowing in the early afternoon.

Começámos a trabalhar juntos em 2019.

We started working together in 2019.

Imperfect — "was starting to / used to start"

Subject	começar (imperfect)	Example with perceber
eu	começava	começava a perceber
tu	começavas	começavas a perceber
ele / ela / você	começava	começava a perceber
nós	começávamos	começávamos a perceber
eles / elas / vocês	começavam	começavam a perceber

Quando o fui buscar, já começava a anoitecer.

When I went to pick him up, it was already starting to get dark.

Eles começavam a desconfiar que algo estava errado.

They were starting to suspect something was wrong.

Future and conditional

Vou começar a estudar para o exame amanhã de manhã.

I'm going to start studying for the exam tomorrow morning.

A partir de setembro, começarei a trabalhar em part-time.

Starting in September, I'll begin working part-time.

Se tivesse mais tempo, começaria a aprender piano.

If I had more time, I'd start learning piano.

Subjunctive

Antes que comeces a gritar, deixa-me explicar.

Before you start shouting, let me explain.

Esperamos que comeces a sentir-te melhor em breve.

We hope you start feeling better soon.

Triggered temporal contexts

Começar a + inf is especially natural in sentences that pin down the beginning point. Three anchor patterns recur over and over in real EP:

Há + time — "X ago": Comecei a fumar há dez anos.
A partir de + date — "starting from": A partir de janeiro, começo a correr todas as manhãs.
Aos + age — "at the age of": Aos seis anos, começou a tocar piano.

Há quantos anos começaste a tocar guitarra?

How many years ago did you start playing guitar?

Aos catorze anos comecei a trabalhar nas férias de verão.

At fourteen I started working during the summer holidays.

A partir da próxima semana, começamos a abrir ao sábado.

Starting next week, we'll begin opening on Saturdays.

Começar a vs começar + gerund — the Brazilian split

Brazilian Portuguese sometimes uses começar + gerund (começou estudando, "he began by studying"). European Portuguese does not use this pattern as a productive periphrasis. In EP, "he started studying" is always começou a estudar. The BR gerund variant exists in a narrow idiomatic sense ("he began as / by studying"), but EP prefers a different construction for that nuance and reserves começar a + infinitive for straightforward inchoative meaning.

Meaning	European Portuguese	Brazilian Portuguese
He started studying Japanese.	Começou a estudar japonês.	Começou a estudar japonês. (same) / Começou estudando japonês. (BR colloquial)
She began to cry.	Começou a chorar.	Começou a chorar.

If you are writing EP, reach for começar a + inf by default and never for começar + gerund.

Começar a vs pôr-se a — start vs suddenly start

Pôr-se a + inf is a sister construction with a sharper, more abrupt flavour. It suggests the beginning was sudden, unexpected, or emotionally charged — someone "burst out" doing something rather than gently getting started.

Começar a — neutral starting: the action begins, with no comment on how abruptly.
Pôr-se a — sudden, often surprising or disruptive starting: "burst out," "up and started."

O bebé começou a chorar quando viu o médico.

The baby started crying when she saw the doctor. (neutral)

O bebé pôs-se a chorar sem razão nenhuma.

The baby suddenly burst into tears for no reason. (abrupt, unexpected)

Quando ouviu a notícia, pôs-se a rir.

When he heard the news, he burst out laughing.

Note the reflexive marker in pôr-se a and the tricky preterite pôs-se with its circumflex. See the periphrastic overview for the full paradigm.

Começar a vs passar a — start vs switch to

Passar a + inf is a third relative. It does not mark the beginning of an action in the here-and-now, but the adoption of a new habit or state going forward from some turning point.

Começar a — the action begins, typically as a first-time event or a zoomed-in "now it starts."
Passar a — from this point on, this is how things are done. The speaker is switching to a new routine, often replacing an older one.

Comecei a usar óculos aos doze anos.

I started wearing glasses at twelve. (the first time I needed them)

Depois da operação, passei a usar lentes de contacto.

After the surgery, I switched to wearing contact lenses. (adopted as new habit)

Começámos a reunir-nos todas as semanas.

We started meeting every week. (the meetings began)

Passámos a reunir-nos todas as semanas em vez de quinzenalmente.

We switched to meeting every week instead of every two weeks. (changed routine)

The English "start" is a trap: in sentences about habit-switching, reach for passar a; in sentences about an initial beginning, reach for começar a.

Negation

Não precedes the conjugated auxiliary.

Não comeces a falar de política à mesa.

Don't start talking about politics at the table.

Os vizinhos não começaram a fazer barulho senão depois da meia-noite.

The neighbours didn't start making noise until after midnight.

Object pronouns

The clitic attaches to the infinitive by default.

Ela começou a escrever-me cartas depois da viagem.

She started writing me letters after the trip.

Comecei a vê-lo como amigo, não como colega.

I started seeing him as a friend, not as a colleague.

Note the infinitive contraction in the second example: ver + o → vê-lo, with the final -r dropping and an l- added to the pronoun.

With a proclisis trigger, the clitic jumps in front of começar.

Não me comeces a chatear com isso outra vez.

Don't start bothering me with that again.

Common mistakes

❌ Começei a estudar em 2019.

Spelling error — before -ei the ç must become plain c: comecei.

✅ Comecei a estudar em 2019.

I started studying in 2019.

❌ Começamos a trabalhar juntos em 2019.

Ambiguous out of context — without the accent, this reads as present ('we are starting to work together in 2019'). For the past use começámos.

✅ Começámos a trabalhar juntos em 2019.

We started working together in 2019.

❌ Começou estudando japonês aos dez anos.

Brazilian pattern — in EP use começar a + infinitive.

✅ Começou a estudar japonês aos dez anos.

He started studying Japanese at ten.

❌ Começo estudar amanhã.

Missing the linker — começar requires a before the infinitive.

✅ Começo a estudar amanhã.

I start studying tomorrow.

❌ Comecei a usar lentes depois da operação.

Works, but implies this was the first time you ever used lenses. If you are switching habits, passar a is more idiomatic.

✅ Passei a usar lentes depois da operação.

I switched to wearing contacts after the operation.

Key takeaways

Form: conjugated começar
- a (plain preposition) + bare infinitive.
Meaning: inchoative — the action begins. Neutral with respect to abruptness.
Spelling: watch ç → c before e (comecei) and the acute on the nós preterite (começámos).
Do not use começar + gerund in EP — it is a Brazilian colloquial pattern, not a native EP construction.
Relatives: pôr-se a + inf = suddenly / burst into doing; passar a + inf = switch to / adopt as new habit; continuar a + inf = keep on doing (see continuar a + infinitive).
Clitics: enclitic to the infinitive by default (começar a escrever-me), proclitic with a trigger (não me comeces a chatear).