Learn Hardcore Portuguese (Portugal): Eu não quero entrar no carro sujo.

The verb entrar normally uses the preposition em (to enter in/into something).
Since carro is masculine singular and we are talking about the car, we need em + o carro → this contracts to no carro.

So entrar no carro literally is to enter in the car, which is how Portuguese naturally says to get into the car.

Why is sujo after carro and not before it?

In Portuguese, adjectives usually come after the noun:

carro sujo = dirty car
casa grande = big house
livro interessante = interesting book

Putting the adjective before the noun is possible in some cases, but it often adds a special nuance (more emotional, poetic, or idiomatic), and sujo carro would sound strange or literary at best.

So the normal, neutral order is carro sujo.

Do I really need the eu, or can I just say Não quero entrar no carro sujo?

You do not need eu. Both are correct:

Eu não quero entrar no carro sujo.
Não quero entrar no carro sujo.

Portuguese is a pro‑drop language, meaning the subject pronoun is often omitted because the verb ending (-o in quero) already shows it’s I.

Using eu can:

add emphasis (as in I don’t want to…)
make the subject clearer in longer or more complex sentences

But in an isolated sentence, Não quero entrar no carro sujo is completely natural.

Why does não go before quero? Could I say Eu quero não entrar no carro sujo?

The normal position for não is immediately before the verb it negates:

Eu não quero entrar… = I do not want to enter…

Eu quero não entrar… is grammatically possible, but the meaning shifts:

Eu não quero entrar no carro sujo.
= I don’t want to get into the dirty car. (the wanting is negated)
Eu quero não entrar no carro sujo.
= I want not to get into the dirty car. (this sounds more deliberate or contrastive, like you’re choosing not to enter as a specific option)

In everyday speech, the first version (não quero entrar) is by far the most common.

Why is it quero and not querer?

Querer is the infinitive form (to want).
Here, we need the verb conjugated in the present tense, 1st person singular:

Conjugation of querer (eu/tu/ele… in European Portuguese):

eu quero – I want
tu queres – you (informal, singular) want
ele / ela quer – he / she wants
nós queremos – we want
vocês querem – you (plural) want
eles / elas querem – they want

So Eu não quero… = I do not want…
Using Eu não querer… would be ungrammatical in this context.

Why is it entrar and not entro after quero?

After verbs like querer (to want), poder (can), conseguir (manage to), etc., Portuguese normally uses the infinitive for the second verb:

Eu quero entrar. = I want to enter.
Eu posso entrar. = I can enter.
Eu consigo entrar. = I manage to enter.

If you said Eu não quero entro, it would be incorrect.
You need quero + infinitive, so quero entrar is the right form.

Why can’t I say entrar o carro sujo without a preposition?

Because entrar in Portuguese is not used with a direct object like that. It is either:

intransitive: entrar (to enter)
or used with a preposition: entrar em (to enter in/into)

So with a place or vehicle, you say:

entrar em casa → entrar em casa
entrar em o carro → entrar no carro

Entrar o carro would sound like to enter the car as a direct object, which is not how the verb works in Portuguese.
You must have em (which here appears as the contraction no).

Does no carro mean in the car or into the car?

It can mean in or into, depending on context. Portuguese often uses the same structure entrar em to express both:

entrar no carro = get into the car
entrar na casa = go into the house

The verb entrar itself already implies movement into, so entrar no carro is best understood as to get into the car rather than just to be in the car.

To express simply being in, you would normally use estar:

Estou no carro. = I am in the car.

Why is it carro sujo and not carros sujos or carro suja?

Adjectives in Portuguese agree with the gender and number of the noun:

carro = masculine singular
→ carro sujo (dirty car)
carros = masculine plural
→ carros sujos (dirty cars)
casa = feminine singular
→ casa suja (dirty house)
casas = feminine plural
→ casas sujas (dirty houses)

In your sentence, we are talking about one car (carro) and the noun is masculine, so:

o carro sujo = the dirty car (masc. singular)

Can carro sujo also mean the car is dirty now (a specific car, right here), or is it more general?

Carro sujo on its own just means dirty car; context decides whether it’s:

a particular car that is dirty right now
- Não quero entrar no carro sujo. → the car we’re looking at is dirty
or a generic description
- Nunca entro em carro sujo. → I never get into a dirty car (any car that is dirty)

In your sentence, with the article no carro sujo, it most naturally refers to a specific car both speaker and listener know about (for example, the one in front of you).

How is não pronounced in European Portuguese?

Key points for não in European Portuguese (EP):

The ã is a nasal vowel (similar to the vowel in French sans, but shorter).
The o at the end is not pronounced like a full o; it often sounds more like a weak, nasalized u or is very reduced.
The final m in nasal syllables (as in não, written with ão) is not pronounced as an English m, but it marks the nasalization of the vowel.

So não is roughly like nahw̃ or naw̃, with the vowel nasalized.
In fast EP speech, Eu não quero can sound like [eũ nãu kɛru], with a clear nasal sound on não.

How should I pronounce carro in European Portuguese?

In European Portuguese:

The rr in carro is usually a strong guttural sound, made at the back of the throat (similar to the French r in rue, or a kind of harsh h).
The stress is on the first syllable: CÁ‑rro.
The final o is often slightly reduced, not a very strong oh sound.

So carro is something like KÁ‑hru (with that guttural r).

Is this sentence the same in Brazilian Portuguese, or is there a difference for Portugal?

The sentence Eu não quero entrar no carro sujo. is perfectly natural in both European Portuguese (Portugal) and Brazilian Portuguese.

Main differences would be:

Pronunciation:
- EP: more vowel reduction and a guttural r.
- BP: clearer vowels, and depending on region, r may be a guttural sound or a flapped/trilled r.
Possible everyday alternatives:
- BP speakers might also often say entrar no carro or entrar no carro sujo just like EP.

But grammatically and lexically, your sentence works fine in both varieties.

Could I say entrar para o carro sujo instead of entrar no carro sujo?

No, not in normal usage. With entrar meaning to go into / get into, the correct preposition is em, which here appears as no (em + o).

entrar em o carro sujo → entrar no carro sujo

Entrar para o carro is not idiomatic for get into the car.
You might see entrar para in other senses (e.g. entrar para a universidade = to get into university, as in being admitted), but for a physical space/vehicle, use em → no / na / nos / nas.

Does word order change the meaning if I say Eu não quero entrar sujo no carro instead?

Yes, that changes the meaning.

Eu não quero entrar no carro sujo.
= I don’t want to get into the dirty car.
(the car is dirty)
Eu não quero entrar sujo no carro.
= I don’t want to get into the car dirty.
(I am dirty; I don’t want to enter the car in a dirty state)

So:

carro sujo → the car is dirty
entrar sujo → I am dirty when I enter

Both are correct, but they describe different things as dirty.