O vencedor recebeu mil euros.

O means the. It is the masculine singular definite article, and it matches vencedor, which is a masculine singular noun.

So:

• o vencedor = the winner

In Portuguese, articles are used very regularly, often more than in English.

Yes. Vencedor is a masculine singular noun meaning winner.

Its forms are:

• o vencedor = the male winner / the winner
• a vencedora = the female winner
• os vencedores = the winners
• as vencedoras = the female winners

Like many Portuguese nouns, it changes form to match gender and number.

The infinitive is receber, meaning to receive.

A few useful forms are:

• receber = to receive
• recebo = I receive
• recebe = he/she receives
• recebeu = he/she received

Recebeu is the preterite (simple past) of receber.

It is used for a completed action in the past:

• O vencedor recebeu mil euros. = The winner received one thousand euros.

This suggests a finished event: the money was received.

Because recebeu refers to a single completed action.

Compare:

• recebeu = received, got once, completed event
• recebia = was receiving / used to receive / received repeatedly or as background information

So in this sentence, recebeu is the natural choice because it describes one finished result.

In Portuguese, 1000 is normally just mil, not um mil.

So:

• mil euros = one thousand euros
• dois mil euros = two thousand euros

Mil does not change form here.

Because the amount is greater than one.

Compare:

• um euro
• dois euros
• mil euros

Just like in English, the currency noun is plural after numbers above one.

Yes, you can, but the nuance is slightly different.

• recebeu mil euros = received one thousand euros
• ganhou mil euros = won/earned one thousand euros

Recebeu focuses on the fact that the money was received. Ganhou focuses more on winning or obtaining it as a prize.

In many contexts, both are possible.

Yes. This is the normal, neutral Portuguese word order:

• O vencedor = subject
• recebeu = verb
• mil euros = direct object

So the structure is:

subject + verb + object

You can change the order for emphasis, but the given sentence is the most natural standard version.

Normally, no, not in ordinary standard speech.

O vencedor recebeu mil euros is the normal sentence.

Without the article, Vencedor recebeu mil euros sounds more like a headline, note, or very reduced style. In everyday Portuguese, you would usually keep o.

In European Portuguese, recebeu is pronounced approximately like ruh-suh-BEU, although that is only a rough guide for an English speaker.

A few useful points:

• the final -eu sounds like a diphthong
• unstressed vowels in European Portuguese are often reduced
• the stress falls on the last syllable: re-ce-BEU

So the stressed part is beu.

The sentence itself is the same and is perfectly correct in Brazilian Portuguese too:

• O vencedor recebeu mil euros.

The main difference is pronunciation. Also, in a Brazilian context, you would more often see Brazilian currency, such as reais, instead of euros, unless the context specifically involves euros.