Learn Hardcore Portuguese (Portugal): A Ana achou estranho eu chegar tão cedo à aula. - Ana found it strange that I arrived so early to class.

You can say just Ana achou estranho…, and it’s not wrong, but in European Portuguese it may sound a bit more written/formal or stylistic. In everyday speech, A Ana is more typical.

In Brazilian Portuguese, using the article with names is less universal and varies by region; in European Portuguese it’s much more standard.

What is the role of achou estranho here? Is it like “found it strange” or “thought it was strange”?

Exactly. Achar often means to think / to find (opinion), not only to find (locate).

A Ana achou estranho…
= Ana thought it was strange / Ana found it strange…

The structure is:

A Ana (subject)
achou (verb in the simple past – pretérito perfeito)
estranho (adjective: strange)
eu chegar tão cedo à aula (thing she found strange)

So you can read it as:

A Ana achou (isso) estranho: eu chegar tão cedo à aula.
= Ana found this strange: my arriving so early to class.

Why is it eu chegar and not eu cheguei?

Because eu chegar is an inflected infinitive (infinitivo pessoal), not a finite verb.

eu cheguei = I arrived (past, finite verb)
eu chegar = my arriving / me arriving (non‑finite, acting like a noun phrase)

The part eu chegar tão cedo à aula behaves like a clause as a thing:

A Ana achou estranho [eu chegar tão cedo à aula].
≈ Ana found [my arriving so early to class] strange.

English uses my arriving / me arriving; Portuguese uses eu chegar.

If you used eu cheguei, you would start a new clause with a normal finite verb and you’d need something like:

A Ana achou estranho que eu cheguei tão cedo à aula.
(which in standard Portuguese would normally be:
A Ana achou estranho que eu tivesse chegado tão cedo à aula. – with subjunctive)

What exactly is the infinitivo pessoal in eu chegar? When is this form used?

The infinitivo pessoal (personal / inflected infinitive) is a special Portuguese form where the infinitive shows the subject:

chegar – to arrive (plain infinitive)
eu chegar – I (to) arrive / my arriving
tu chegares – you (to) arrive / your arriving
ele/ela chegar – he/she (to) arrive
nós chegarmos – we (to) arrive
vocês/eles chegarem – you/they (to) arrive

It’s used when:

The subject of the infinitive is explicit or different from the subject of the main verb:
- A Ana achou estranho eu chegar tão cedo.
  (subject of achar = Ana; subject of chegar = eu)
The clause with the infinitive functions as a “thing”: subject, object, complement, etc.:
- É importante nós chegarmos cedo.
- Ela prefere eles ficarem em casa.

In your sentence, eu chegar tão cedo à aula is an object of achou estranho, and the subject is eu, so the infinitivo pessoal is appropriate.

Could we use a que-clause instead, like que eu chegasse? What’s the difference?

Yes, there is a very natural alternative:

A Ana achou estranho eu chegar tão cedo à aula.
A Ana achou estranho que eu chegasse tão cedo à aula.

Both are correct and idiomatic.

Difference in feel (European Portuguese):

Infinitivo pessoal (eu chegar)
– Slightly more concise, often feels a bit more neutral or matter‑of‑fact.
– Very common in European Portuguese in this type of sentence.
Subjunctive clause (que eu chegasse)
– A bit more explicitly clausal and can sound a bit more formal or written in some contexts.
– Subjunctive highlights that this is in the speaker’s opinion / perspective.

Meaning-wise, in this sentence they’re essentially equivalent: Ana thought my arriving so early was strange.

Why do we include eu? Could we just say A Ana achou estranho chegar tão cedo à aula?

You can drop eu, but the meaning becomes less specific.

A Ana achou estranho eu chegar tão cedo à aula.
= She thought my arriving so early was strange.
A Ana achou estranho chegar tão cedo à aula.
= She thought it was strange to arrive so early to class (in general).
It doesn’t clearly say who is doing the arriving; it could be her, me, people in general, depending on context.

In Portuguese you normally omit subject pronouns with finite verbs (e.g. cheguei instead of eu cheguei), but with the infinitivo pessoal, it’s common and often necessary to show the subject explicitly, to avoid ambiguity.

Why is estranho masculine singular? Shouldn’t it agree with Ana or aula?

Estranho here does not describe Ana or aula directly; it describes the situation / fact of you arriving early.

Portuguese often uses masculine singular adjectives for abstract or “neutral” ideas:

É estranho eu chegar tão cedo. – It is strange that I arrive so early.
É importante nós chegarmos cedo.

In A Ana achou estranho eu chegar tão cedo à aula, the logical structure is:

Ana found (it) strange: my arriving so early.

That “it” (the fact/situation) is represented by estranho in the default, neutral masculine singular form.

Why is it à aula and not na aula or para a aula?

The verb chegar in standard European Portuguese normally takes the preposition a for destination:

chegar a casa – arrive home
chegar à escola – arrive at school
chegar à aula – arrive at the class/lesson

Now, a (to) + a (the, feminine singular) contracts to à with a grave accent:

chegar a + a aula → chegar à aula

So:

à aula = to the class / to the lesson / at the class (as a destination)

Na aula = em + a aula – “in the class / in the lesson”.
That describes location, not destination:

Estou na aula. – I am in class.

Para a aula would be towards / for the class; it can work in some contexts but with chegar, the idiomatic preposition in EP is a (→ à).

What does the accent in à mean? Is it pronounced differently from a?

The grave accent (à) here marks a contraction (crase) of two a’s:

preposition a (to)
article a (the, feminine singular)

So:

a + a aula → à aula

Pronunciation: in European Portuguese, a and à are pronounced the same in this context; the accent is orthographic, not phonetic here.

Compare:

Vou a casa. – I go to home (no article).
Vou à aula. – I go to the class (with article).

Could I say tão cedo as muito cedo? What’s the difference?

Both are possible, but they’re not identical:

tão cedo = so early / that early
Often implies surprise or emotional reaction, and sometimes relates to an earlier context (e.g. I didn’t expect it this early).
muito cedo = very early
Focuses more on the degree of earliness itself.

In your sentence:

A Ana achou estranho eu chegar tão cedo à aula.
= Ana found it strange that I arrived so early (earlier than expected).

Muito cedo would still be understandable, but tão cedo fits better with achar estranho, because it underscores the unexpectedness.

How would this sentence look in the present instead of the past?

Just change achou (preterite) to acha (present):

A Ana achou estranho eu chegar tão cedo à aula.
= Ana found it strange that I arrived so early to class.
A Ana acha estranho eu chegar tão cedo à aula.
= Ana finds it strange that I arrive so early to class.
(e.g. this happens regularly, and she generally finds it strange)

Could I use another verb like esquisito instead of estranho? Are they the same?

Esquisito is an adjective, not a verb, and it’s close in meaning to estranho, but a bit more colloquial and often more negative/weird‑sounding:

estranho – strange, unusual
esquisito – weird, odd (often stronger / more informal)

You could say:

A Ana achou esquisito eu chegar tão cedo à aula.

Meaning: Ana thought it was weird that I arrived so early to class.
So yes, it works, just with a slightly different tone (more like “weird” than neutral “strange”).

The verb remains achou; you’re only changing the adjective (estranho → esquisito).

Why don’t we say de eu chegar like in English “for me to arrive”?

English often uses for + person + to‑verb:

It’s strange for me to arrive so early.

Portuguese does not mirror that with de in this structure. You normally say:

É estranho eu chegar tão cedo.
(not: É estranho de eu chegar…)

Similarly:

A Ana achou estranho eu chegar tão cedo à aula.

Using de here (estranho de eu chegar) is non‑standard and sounds incorrect in modern Portuguese. The infinitivo pessoal with the subject (eu chegar) connects directly to estranho without extra prepositions.

Can I change the word order of tão cedo, like eu tão cedo chegar à aula?

Native speakers would almost always keep tão cedo right after chegar:

✅ eu chegar tão cedo à aula – natural
❌ eu tão cedo chegar à aula – sounds unnatural / poetic at best

You can move tão cedo a bit, but not freely. These are acceptable:

A Ana achou estranho eu chegar tão cedo à aula.
A Ana achou estranho eu chegar à aula tão cedo. (slight change of rhythm/emphasis)

But eu tão cedo chegar… feels wrong in normal speech. The default, most natural option is the original word order.