Learn Hardcore Portuguese (Portugal): Quando ela estaciona, tira o cinto de segurança com cuidado. - When she parks, she takes off the seat belt carefully.

Because it describes a habitual action. In Portuguese, the present indicative after quando is normal for routines or general truths: Quando ela estaciona, tira… For a specific future event, switch to the future subjunctive in the quando-clause: Quando ela estacionar, vai tirar… / tirará…

Could I drop the subject ela?

Yes. European Portuguese often drops subject pronouns when the verb ending shows the subject. Quando estaciona, tira o cinto… is perfectly natural. You would keep ela if you need to avoid ambiguity or add emphasis.

Is the comma after Quando ela estaciona required?

Yes. When a dependent clause (like one with quando) comes first, you use a comma before the main clause: Quando ela estaciona, … If you reverse the order, you typically omit the comma: Ela tira o cinto de segurança com cuidado quando estaciona.

Do I need to say the object of estaciona (e.g., o carro)?

No. Estacionar can be used intransitively when it’s obvious we’re talking about a car: Quando ela estaciona, … If you want to be explicit, you can say Quando ela estaciona o carro, …—both are fine.

What’s the difference between estacionar and parar?

Estacionar = to park (put the vehicle in a parking spot, usually turn off the engine and leave it there).
Parar = to stop (come to a halt, possibly only briefly).
So after you parar at a red light, you wouldn’t normally tirar o cinto; after you estacionar, you would.

Is tirar the best verb here? What about desapertar, soltar, or afrouxar?

Tirar (o cinto) = remove/take off the seat belt (very common and idiomatic).
Desapertar (o cinto) = unfasten the seat belt (focus on the buckle action; also common).
Soltar (o cinto) = release the seat belt (also used).
Afrouxar (o cinto) = loosen the belt (not necessarily remove it).
All work, but tirar and desapertar are the most typical in Portugal.

Why o cinto de segurança and not just o cinto or um cinto?

O cinto de segurança is specific: the seat belt in the car.
O cinto is also fine if context makes it clear you mean the seat belt.
Um cinto would sound like some belt (not the one you’re wearing in the car), so it’s not natural here.

Why de segurança and not da segurança?

Portuguese often forms compound-noun expressions with de without an article when the second noun classifies the first: cinto de segurança, sapatos de corrida, óculos de sol. Da segurança would mean “of the security,” which isn’t the intended classifier here.

If I replace o cinto de segurança with a pronoun, where does it go and how is it written?

In European Portuguese, in affirmative clauses without a clitic trigger, the object pronoun is enclitic (after the verb) with a hyphen:

Quando ela estaciona, tira-o com cuidado.
If you add a trigger like não, it goes before the verb (proclisis):
Quando ela estaciona, não o tira imediatamente.

Could I say Quando ela estaciona, o tira com cuidado?

In European Portuguese, that proclitic position (before the verb) is usually used only if there’s a proclisis trigger (e.g., não, certain adverbs, negatives, relatives, etc.). Here, there isn’t one, so the default is enclisis: … tira-o… In Brazil, pronoun placement is different and o tira is more acceptable, but even there people often avoid clitics and just repeat the noun phrase.

Can I use cuidadosamente instead of com cuidado?

Yes: cuidadosamente means “carefully,” but it’s more formal or written. Com cuidado is very idiomatic and more common in everyday speech. Other natural options: com atenção, com calma (slightly different nuances).

Can I move com cuidado to another position?

Yes. All of these are possible, with minor differences in emphasis:

Tira o cinto de segurança com cuidado. (neutral, most common)
Com cuidado, tira o cinto de segurança. (fronted for emphasis on the manner)
Tira, com cuidado, o cinto de segurança. (parenthetical; more written)
Tira cuidadosamente o cinto de segurança. (more formal)
Placing com cuidado between verb and object (e.g., tira com cuidado o cinto…) is possible but less common in everyday speech.

Is there a future-tense version with quando?

Yes. For a specific future time, use the future subjunctive in the quando-clause:

Quando ela estacionar, vai tirar o cinto de segurança.
Quando ela estacionar, tirará o cinto de segurança.
Your sentence with present tense expresses a general habit.

Is there an alternative with ao + infinitive?

Yes. Ao estacionar, tira o cinto de segurança com cuidado. This means “upon parking” and is common in Portugal, slightly more formal/concise than Quando… for habitual sequences.

How do I conjugate the verbs here in the present (Portugal)?

Both are regular -ar verbs. Present indicative:

estacionar: eu estaciono; tu estacionas; ele/ela estaciona; nós estacionamos; vocês/eles/elas estacionam
tirar: eu tiro; tu tiras; ele/ela tira; nós tiramos; vocês/eles/elas tiram

Any quick pronunciation tips for European Portuguese?

Approximate EP pronunciations:

Quando ≈ KWAHN-doo (final -o sounds like “oo”)
ela ≈ EH-lɐ
estaciona ≈ (ɨ)sh-tah-SYO-nɐ (initial e is very reduced; s before t sounds like “sh”)
tira ≈ TEE-ɾɐ (with a quick tapped r)
o ≈ oo
cinto ≈ SEEN-too (final -o ≈ “oo”)
de ≈ d(uh)/dɨ (very reduced)
segurança ≈ s(uh)-goo-RAHN-sɐ (the “an” is nasal)
com ≈ kong (nasal)
cuidado ≈ kwee-DAH-doo (intervocalic d is soft)