A oficina enviou o orçamento.

Because Portuguese nouns have grammatical gender.

• oficina is a feminine noun, so it takes a: a oficina
• orçamento is a masculine noun, so it takes o: o orçamento

These are the singular definite articles, equivalent to the in English:

• o = the (masculine singular)
• a = the (feminine singular)

So the articles have to match the gender of the noun.

In Brazilian Portuguese, oficina often means a workshop, especially a repair shop.

Depending on context, it can refer to:

• an auto repair shop
• a machine shop
• a workshop where things are fixed or made

In everyday Brazilian usage, if someone says a oficina with no extra context, many people will think of a repair shop, often for cars or motorcycles.

Enviou is the simple past (called the preterite in Portuguese) of the verb enviar.

It is the third person singular form, so it can mean:

• he sent
• she sent
• it sent
• you sent (formal você)

In this sentence, the subject is a oficina, so enviou means sent.

Compare:

• envia = sends / is sending
• enviava = used to send / was sending
• enviou = sent

Because enviar is an -ar verb, and in the preterite, the third person singular ending for regular -ar verbs is usually -ou.

For example:

• falar → falou = spoke
• mandar → mandou = sent / ordered
• enviar → enviou = sent

So enviou follows a very common pattern.

Portuguese uses definite articles more often than English does.

So o orçamento is very natural, especially when referring to a specific estimate, quote, or budget that both sides already know about.

• A oficina enviou o orçamento. = The shop sent the estimate / quote.
• A oficina enviou orçamento. sounds incomplete or unnatural in most normal situations.

In many cases, Portuguese prefers the + noun where English might sometimes just use the noun.

It can mean all of those depending on context.

Most common possibilities:

• budget
• estimate
• quote

In the context of a oficina (a repair shop), orçamento usually means:

• estimate
• price quote

So in a repair-shop situation, A oficina enviou o orçamento would often be understood as:

• The shop sent the estimate.
• The shop sent the quote.

Yes. Mandou is also very common in Brazilian Portuguese.

Both can work:

• enviou = sent
• mandou = sent

But there can be a slight nuance:

• enviar sounds a bit more neutral or formal
• mandar is very common in everyday speech and can sound more informal

So:

• A oficina enviou o orçamento. = slightly more formal/neutral
• A oficina mandou o orçamento. = very natural in conversation

Yes, it can, if the context makes the subject clear.

Portuguese often allows the subject to be omitted:

• A oficina enviou o orçamento.
• Enviou o orçamento.

The full version is clearer on its own, but the shorter version is natural if everyone already knows who sent it.

That said, because enviou could refer to different third-person subjects (he/she/it/you formal), keeping a oficina can help avoid ambiguity.

The normal word order here is:

subject + verb + object
A oficina + enviou + o orçamento

That is the most neutral and natural order.

Other orders are possible, but they usually sound marked or emphasize something:

• O orçamento, a oficina enviou. = The estimate, the shop sent it.
• Enviou a oficina o orçamento. = possible in very formal or literary styles, but not natural in everyday Brazilian Portuguese

So for normal use, stick with: A oficina enviou o orçamento.

In Brazilian Portuguese, enviou is pronounced roughly like en-vee-OH, with the stress on the last syllable.

A rough breakdown:

• en = like eng without the hard g, often slightly nasal
• vi = vee
• ou = a sound like oh

So: en-vee-OH

The final -ou in Brazilian Portuguese is often pronounced close to a clear oh sound.

You could say that, but it changes the meaning.

• o orçamento = the estimate / the quote
  A specific one, probably already known in the conversation
• um orçamento = an estimate / a quote
  Any one estimate, or a new one being introduced

So:

• A oficina enviou o orçamento.
  The shop sent the estimate.
  (a specific estimate)

• A oficina enviou um orçamento.
  The shop sent an estimate / a quote.
  (less specific)

Yes, in this case it is feminine, and the ending -a matches that pattern.

But learners should be careful: noun endings are helpful clues, not absolute rules.

For this word:

• oficina is feminine
• so it takes a and adjectives would also agree in the feminine:
  • a oficina mecânica
  • a oficina pequena

So here, the feminine article is not random—it matches the noun’s gender correctly.