Na reunião, o diretor falou do novo projeto.

Because Portuguese normally contracts em + a into na.

• em = in / at
• a = the (feminine singular)
• na = in the / at the

So:

• na reunião = at the meeting / in the meeting

This is very common in Portuguese:

• no escritório = em + o
• na escola = em + a
• nos livros = em + os
• nas casas = em + as

You know it because the correct article is a: a reunião.

In Portuguese, noun endings do not always reliably tell you the gender, so it is best to learn nouns together with their article:

• a reunião
• o projeto
• o diretor

This is especially important with words ending in -ão, because they can be either masculine or feminine:

• o irmão
• o coração
• a televisão
• a reunião

So here, because it is a reunião, em + a becomes na.

Na reunião is an introductory phrase that sets the scene: it tells us where/when the action happened.

The comma is used to separate that opening phrase from the main clause:

• Na reunião, o diretor falou do novo projeto.

This is natural and clear. In many cases, especially with short introductory phrases, Portuguese can also omit the comma:

• Na reunião o diretor falou do novo projeto.

Both are possible, but the version with the comma gives a slightly clearer pause.

Because Portuguese usually uses the definite article with a specific person or thing in a normal sentence.

• o diretor = the director

In English, you sometimes omit articles in places where Portuguese would not. In Portuguese, saying just diretor here would sound incomplete or unnatural in ordinary prose.

So:

• o diretor falou... = the director spoke...

If it were not a specific director, you could have:

• um diretor = a director

Falou is the pretérito perfeito simples of falar.

It is:

• 3rd person singular
• used for a completed action in the past

So:

• ele falou = he spoke / he talked

In this sentence, o diretor falou means the speaking happened and is seen as a finished event.

A few forms of falar in this tense:

• eu falei
• tu falaste
• ele/ela falou
• nós falámos
• vós falastes
• eles/elas falaram

Here, do is the contraction of de + o.

• de can mean about / of
• o = the
• do = about the / of the

With the verb falar, Portuguese very often uses falar de to mean to talk about.

So:

• falou do novo projeto = talked about the new project

This is one of the most useful patterns to remember:

• falar de alguma coisa = to talk about something

Yes. Falou sobre o novo projeto is also correct.

Both are possible, but there is a slight difference in feel:

• falar de = very common, natural, everyday way to say talk about
• falar sobre = also means talk about, but can sound a bit more explicit or slightly more formal

In European Portuguese, falar de is extremely common in normal speech.

There is also:

• falar em = often to mention

So these can differ slightly:

• falou do projeto = talked about the project
• falou sobre o projeto = spoke about the project
• falou no projeto = mentioned the project

In Portuguese, adjectives can often go before or after the noun, but the position may change the nuance.

• novo projeto is the most natural, neutral way to say new project
• projeto novo is possible, but it can sound more contrastive or more focused on the idea that the project is new rather than old

For a learner, the safest choice here is:

• o novo projeto

That is the normal order you will hear very often with novo.

Yes. Portuguese allows some flexibility in word order.

For example:

• Na reunião, o diretor falou do novo projeto.
• O diretor falou do novo projeto na reunião.

Both are correct. The difference is mainly one of focus:

• Na reunião, ... puts the meeting first and sets the scene
• O diretor falou ... na reunião starts with the subject and adds the setting later

The original sentence sounds very natural because it begins with the context.

Usually, yes, in a sentence like this.

• falou do novo projeto most naturally means talked about the new project

Depending on context, English might sometimes translate it as:

• spoke about
• talked about
• mentioned

But the core idea is that the director was speaking on that topic. In most learner contexts, talked about the new project is the best match.

Yes, they matter a lot.

In reunião, the ending -ão is a very common Portuguese ending and it is pronounced as a nasal sound. The accent marks are not optional decoration; they are part of the spelling and pronunciation.

So you should write:

• reunião

not:

• reuniao

For learners, it is worth recognizing -ão as a very common pattern in Portuguese:

• reunião
• informação
• decisão
• situação

In European Portuguese, this ending has a distinct nasal pronunciation that English does not really have in the same way.