Learn Hardcore Portuguese (Brazil): Por favor, limpe o banheiro agora, porque os convidados vão chegar. - Please clean the bathroom now, because the guests are going to arrive.

Limpe o banheiro = polite / neutral command to você
Limpa o banheiro = command to tu (mainly in some regions) or very colloquial to você, but grammatically it’s the tu form.

The sentence is being polite: Por favor, limpe o banheiro agora...

How would this sentence change if I were speaking very informally to a close friend?

You’d probably hear something like:

Limpa o banheiro agora, por favor, porque os convidados vão chegar.

Changes:

limpe → limpa (informal everyday speech, often used even with você)
por favor can stay or be dropped, depending on how polite you want to sound.

If you actually use tu (common in parts of Brazil), the “correct” full version would be:

Por favor, limpa o banheiro agora, porque os convidados vão chegar.
Or even: Por favor, limpa o banheiro agora, porque os convidados vão chegar, tá? (very casual)

Where can I put por favor in the sentence? Does it have to be at the beginning?

It doesn’t have to be at the beginning. All of these are natural:

Por favor, limpe o banheiro agora, porque os convidados vão chegar.
Limpe o banheiro agora, por favor, porque os convidados vão chegar.
Limpe o banheiro agora porque, por favor, os convidados vão chegar. (possible, but unusual/stylistic)

Most common:

At the beginning
- Por favor, limpe o banheiro agora, porque os convidados vão chegar.
After the verb phrase
- Limpe o banheiro agora, por favor, porque os convidados vão chegar.

The position may slightly change the tone, but the meaning is the same: a polite request.

Why do we say o banheiro and not just banheiro?

Portuguese uses definite articles (o, a, os, as) more often than English uses “the”.

o banheiro = the bathroom
Saying just banheiro (without article) is possible, but less common in this specific context and can sound incomplete or telegraphic.

Examples:

Vou ao banheiro. = I’m going to the bathroom.
Limpe o banheiro. = Clean the bathroom (a specific bathroom: the one in the house, at work, etc.).

You’d drop the article more in signs or labels:

Banheiro (on a door sign)
Banheiro masculino / Banheiro feminino

In normal speech, o banheiro is expected.

Could I say “limpe o banheiro já” instead of “agora”?

Yes, but the tone changes a bit.

agora = now, neutral
já = literally already, but in commands it often means right now / immediately and can sound more urgent or more impatient.

Comparing:

Por favor, limpe o banheiro agora, porque os convidados vão chegar.
→ Polite, neutral urgency.
Por favor, limpe o banheiro já, porque os convidados vão chegar.
→ Still polite (with por favor), but stronger: Please clean it right now, the guests are going to arrive.

Why is it porque (one word) and not por que, por quê, or porquê?

In this sentence, porque introduces a reason (because), so it’s written as one word.

Quick guide:

porque (one word)
→ used for because or why in indirect questions
→ Use here: because the guests are going to arrive.
por que (two words)
→ usually in direct questions: why?
→ Por que os convidados vão chegar tão cedo? = Why are the guests going to arrive so early?
por quê (with accent, separated)
→ por que
- at the end of a sentence or alone
  → Eles vão chegar tarde, e eu não sei por quê. = …and I don’t know why.
porquê (one word, with accent)
→ noun meaning reason
→ Ninguém me explicou o porquê. = Nobody explained the reason to me.

So in “porque os convidados vão chegar”, it’s porque = because.

Why do we say os convidados vão chegar instead of using a simple future like chegarão?

Both are grammatically correct:

os convidados vão chegar
os convidados chegarão

But in modern Brazilian Portuguese, the “ir + infinitive” form is much more common in speech:

vão chegar = are going to arrive / will arrive
(literally: they go to arrive)

The simple future chegarão:

sounds more formal, written, or literary;
is less frequent in everyday conversation.

So:

Os convidados vão chegar. = most natural in spoken Brazilian Portuguese.
Os convidados chegarão. = perfectly correct, but more formal/serious style.

Does os convidados mean “the guests” or “the invitees”? Is there any difference?

Convidados literally means people who have been invited, but in most contexts it just means guests.

convidado / convidada = male / female guest
convidados = guests (mixed group or male group)
convidadas = guests (all female)

In a sentence like:

Porque os convidados vão chegar.

English will usually translate it as:

because the guests are going to arrive.

“Invitees” exists in English but is formal/rare. Portuguese convidados is everyday, normal language.

Is the comma before porque necessary?

In everyday writing, both are often seen:

Por favor, limpe o banheiro agora, porque os convidados vão chegar.
Por favor, limpe o banheiro agora porque os convidados vão chegar.

The comma is often used when the second part (porque os convidados vão chegar) is felt as an additional explanation or afterthought. Without the comma, it reads as one smoother sentence.

So:

With comma: adds a slight pause, like “Clean it now, because…”
Without comma: more continuous.

In practice, Brazilians are flexible here; you’ll see both.

How do you pronounce banheiro and what’s going on with that nh?

Banheiro is pronounced roughly like:

[bahn-YEH-roo] (Brazilian approximation)

Breakdown:

ba → like “bah”
nhe → nh is like the “ny” in “canyon” or Spanish ñ
So nhe ≈ “nyeh”
ro → Brazilian r varies by region; often like h in “house” or a soft guttural sound.

So: ba-nhei-ro → bahn-YEH-roo (final -o is not as strong as English “oh”).

How do you pronounce vão and what is that tilde (~) over the a?

Vão is pronounced approximately:

[vā̃w] (like “vown” in English “down”, but nasal)

The tilde (~) over ã indicates a nasal vowel.

vão ≈ “vown” (but keep the vowel nasal, and the final -o is not fully pronounced as “oh”)

Nasal vowels are very important in Portuguese, and the tilde is one of the marks that shows them:

mão (hand)
não (no / not)
irmã (sister)

Could I say this sentence in a more formal way, for example to someone I respect a lot?

Yes. You could use o senhor / a senhora to be more formal:

Por favor, o senhor poderia limpar o banheiro agora? Os convidados vão chegar.
Por favor, a senhora poderia limpar o banheiro agora? Os convidados vão chegar.

Even more polite structure:

Por favor, limpe o banheiro agora, porque os convidados vão chegar.
(already polite, but neutral)
Por favor, você poderia limpar o banheiro agora? Porque os convidados vão chegar.
(softer request, uses conditional poderia = “could you”)

If I change the order to “Porque os convidados vão chegar, por favor limpe o banheiro agora.”, is it still correct?

Yes, it is grammatically correct and natural:

Porque os convidados vão chegar, por favor limpe o banheiro agora.

This word order emphasizes the reason first:

Because the guests are going to arrive, please clean the bathroom now.

Both orders are fine; you just shift what you highlight first:

Request first (more common):
- Por favor, limpe o banheiro agora, porque os convidados vão chegar.
Reason first (emphatic explanation):
- Porque os convidados vão chegar, por favor limpe o banheiro agora.