O relatório foi revisado pela gerente antes da reunião.

Because this sentence is in the passive voice.

• foi revisado = was reviewed / was revised
• The focus is on o relatório (the report), not on who did the action.

Compare:

• O relatório foi revisado pela gerente.
  = The report was reviewed by the manager.
  Passive voice

• A gerente revisou o relatório.
  = The manager reviewed the report.
  Active voice

In Portuguese, a very common passive pattern is:

• ser
  • past participle

So here:

• foi = past of ser
• revisado = past participle of revisar

Revisado is the past participle of revisar.

Depending on context, revisar can mean:

• to review
• to revise
• to check
• sometimes to proofread

In O relatório foi revisado, the best English choice is often was reviewed or was revised, depending on the context you were given.

Because revisado agrees with o relatório, which is masculine singular.

In Portuguese, the past participle used like this usually agrees with the noun it describes in gender and number.

• o relatório → masculine singular → revisado
• a proposta → feminine singular → revisada
• os relatórios → masculine plural → revisados
• as propostas → feminine plural → revisadas

So:

• O relatório foi revisado.
• A proposta foi revisada.

Because gerente can refer to either a man or a woman. The article tells you the gender of the person.

• o gerente = the male manager
• a gerente = the female manager

So in your sentence:

• pela gerente = by the female manager

The noun itself does not change form here; the article changes.

Because por + a contracts to pela.

This is a very common Portuguese contraction:

• por + o = pelo
• por + a = pela
• por + os = pelos
• por + as = pelas

So:

• pela gerente = por a gerente

In passive sentences, por often introduces the agent, just like by in English:

• foi revisado pela gerente = was reviewed by the manager

Because antes normally uses de before a noun.

So the full structure is:

• antes de + a reunião

And de + a contracts to da:

• antes da reunião

Other examples:

• antes do almoço = before lunch
• antes da aula = before class
• antes de sair = before leaving

So antes da reunião literally comes from antes de a reunião, but the natural form is the contraction da.

Da is a contraction of:

• de + a = da

In this sentence:

• antes da reunião = before the meeting

Here are the related forms:

• do = de + o
• da = de + a
• dos = de + os
• das = de + as

These contractions are extremely common in Portuguese.

Yes, it sounds fairly neutral-to-formal, and very natural in written Portuguese.

Why?

• The passive voice (foi revisado) is common in reports, business language, news, and formal writing.
• The noun relatório also sounds like workplace or academic vocabulary.

A more direct, less formal version would be:

• A gerente revisou o relatório antes da reunião.

Both are correct and natural. The passive version simply sounds a bit more impersonal and report-like.

Yes, absolutely. A very common active version is:

• A gerente revisou o relatório antes da reunião.

This means the same thing, but the emphasis changes:

• Passive: focus on the report
• Active: focus on the manager

In everyday speech, Portuguese often prefers the active voice, just like English does. But the passive is also very normal, especially in formal contexts.

It is the simple past passive.

Breakdown:

• foi = third person singular of ser in the pretérito perfeito
• revisado = past participle

So the whole expression means:

• was reviewed
• was revised

It refers to a completed action in the past.

Sometimes, depending on context, yes.

Portuguese and English do not always match tense-for-tense exactly. In many cases, Portuguese uses the simple past where English might choose either:

• was reviewed
• has been reviewed

But in this sentence, because of antes da reunião, the most natural English interpretation is usually:

• was reviewed before the meeting

That clearly places the action before another past event.

Because that is the topic or focus of the sentence.

Since this is a passive sentence, the thing affected by the action comes first:

• O relatório = the thing being reviewed

That is exactly how passive voice works in English too:

• The report was reviewed by the manager.

If you wanted to focus on the person doing the action, you would usually switch to the active voice:

• A gerente revisou o relatório.

In this case, yes: relatório is masculine, and the article o shows that.

• o relatório

The ending -o often suggests a masculine noun, but not always. The safest habit is to learn nouns together with their article:

• o relatório
• a reunião
• a gerente

That helps you remember gender more reliably.

Yes, reunião is a feminine noun:

• a reunião = the meeting

That is why:

• de + a reunião = da reunião

So:

• antes da reunião = before the meeting

Again, it helps to learn the noun with its article:

• a reunião

A simple approximate guide for Brazilian Portuguese:

• relatório ≈ heh-lah-TOH-ryoo
• reunião ≈ heh-oo-nee-OW̃

A few useful notes:

• The r at the beginning of a word in Brazilian Portuguese often sounds like an English h.
• tó in relatório carries the stress: re-la-TÓ-rio
• ão is nasal, which is very important in reunião

A rough stress guide:

• re-la-TÓ-rio
• re-u-ni-ÃO

Yes. Just like English, Portuguese can omit the person who did the action if it is unknown, obvious, or unimportant.

So you can say:

• O relatório foi revisado antes da reunião.

That means:

• The report was reviewed before the meeting.

If you include pela gerente, you are specifically naming who did it.

Yes. Portuguese word order is flexible, especially with time expressions.

All of these are possible:

• O relatório foi revisado pela gerente antes da reunião.
• Antes da reunião, o relatório foi revisado pela gerente.
• O relatório, antes da reunião, foi revisado pela gerente.
  (possible, but less neutral)

The most natural neutral choices are usually:

• O relatório foi revisado pela gerente antes da reunião.
• Antes da reunião, o relatório foi revisado pela gerente.

The first sounds more straightforward. The second puts extra emphasis on the time.

• A relatório is incorrect because relatório is masculine, so it must be o relatório.
• reunião needs the feminine article in this sentence because it appears inside da reunião, where da = de + a.

So the sentence needs:

• O relatório
• da reunião

Portuguese uses articles very often, sometimes more often than English does.

Yes — several useful Portuguese patterns appear here all at once:

1. Passive voice

   • foi revisado = was reviewed

2. Agreement

   • revisado matches o relatório

3. Contractions

   • pela = por + a
   • da = de + a

4. Gender shown by articles

   • o relatório
   • a gerente
   • a reunião

5. Time expression

   • antes da reunião = before the meeting

It is a great sentence for noticing how Portuguese packs grammatical information into articles, participles, and contractions.