Learn Hardcore Portuguese (Portugal): Se passares do teu limite de café, ficas nervoso e estudas pior. - If you go over your coffee limit, you get nervous and study worse.

In European Portuguese, after se (if) when talking about a future condition, you normally use the future subjunctive:
- Se passares do teu limite de café… = If you go over your coffee limit (in the future)…
- Quando passares o exame, vamos festejar. = When you pass the exam, we’ll celebrate.

You would not usually say Se vais passar do teu limite de café in this kind of general rule, and Se passas would sound less standard; Se passares is the canonical pattern for an open future condition.

Why is it Se passares… ficas nervoso e estudas pior and not ficarás nervoso e estudarás pior?

Portuguese often uses the present indicative to talk about general, habitual consequences of a condition:

Se passares do teu limite de café, ficas nervoso e estudas pior.
Literally: If you go over your coffee limit, you get nervous and you study worse.

Using the synthetic future (ficarás, estudarás) would sound too “formal/remote” or overly theoretical here. For general truths and habits, the pattern is:

Se
- future subjunctive (passares)
→ main clause in present indicative (ficas, estudas)

Why do we say passares do teu limite de café and not just passares o teu limite de café?

The verb here is passar de in the sense of to go beyond / to exceed.

passar de um limite = to go over / exceed a limit
- Se passares do teu limite de café… = If you go beyond your coffee limit…

If you drop the de (Se passares o teu limite de café), it sounds odd or wrong in this meaning.
Without de, passar tends to mean to pass, to go past something, not to exceed it in this idiomatic way.

What exactly does do in do teu limite de café stand for?

Do is a contraction:

de + o = do

The structure is:

passar de + o limite = passar do limite
then add the possessive: o limite de café → o teu limite de café
with the preposition: de o teu limite de café → do teu limite de café

So do teu limite de café literally is “of the your coffee limit” (Portuguese requires the article o).

Why is it teu limite de café and not seu limite de café?

In European Portuguese:

teu / tua / teus / tuas = possessive of tu (informal “you”)
seu / sua / seus / suas = typically the possessive of ele / ela / você (he/she/you-formal), and can be ambiguous.

So:

o teu limite de café = your coffee limit (talking directly to someone as tu)
o seu limite de café = usually “his/her/your (formal) coffee limit” (context decides).

For an informal tu, teu is the normal and clear choice in Portugal.

Why is the article o used (inside do teu limite) with the possessive? In English we don’t say “the your coffee limit”.

European Portuguese very often uses a definite article + possessive:

o teu limite
a tua casa
os teus livros

So:

do teu limite de café = de + o teu limite de café

Leaving out the article (de teu limite de café) is grammatically possible in some contexts but feels much less natural and is rarely used in everyday European Portuguese. The pattern article + possessive is the default.

What does limite de café mean literally and in practice?

Literally:

limite = limit
de café = of coffee

So limite de café = coffee limit.

In context, it means something like:

the maximum amount of coffee you can drink (e.g. number of cups) before negative effects start.

You could paraphrase:

Se passares do teu limite de café
→ If you drink more coffee than is good for you…

Why is nervoso masculine? Does it change if I’m a woman?

Nervoso is an adjective that agrees in gender and number with the subject:

ficar nervoso (masculine singular)
ficar nervosa (feminine singular)

In the given sentence, it is written in the masculine as a neutral/default form.
If a woman is talking about herself, she would normally say:

Se passar do meu limite de café, fico nervosa.
(If I go over my coffee limit, I get nervous.)

So yes, it changes to nervosa for a feminine subject.

What part of speech is pior in estudas pior, and why not mais mal?

Here pior is an adverb modifying estudas (“you study”).

Portuguese has irregular comparatives, just like English:

bom → melhor (better)
mau / má → pior (worse)
bem → melhor (better, as an adverb)
mal → pior (worse, as an adverb)

So:

estudas mal = you study badly
estudas pior = you study worse

Mais mal is generally avoided in this kind of comparative; pior is the standard form.

Could we say estudas piormente instead of estudas pior?

No, piormente is either extremely rare or sounds artificial/incorrect in modern Portuguese.

For “worse” as an adverb, you simply use pior:

estudas pior = you study worse
trabalhas pior sob pressão = you work worse under pressure

Using piormente would sound very unnatural.

Why is there a comma after the se‑clause: Se passares do teu limite de café, ficas nervoso…?

In Portuguese, as in English, when a conditional clause with se comes before the main clause, a comma is normally used:

Se passares do teu limite de café, ficas nervoso…
Se chover, ficamos em casa.

If you invert the order, you usually drop the comma:

Ficas nervoso e estudas pior se passares do teu limite de café.

Could we use the present indicative instead of the future subjunctive and say Se passas do teu limite de café?

You might hear Se passas do teu limite de café in informal speech, but:

The standard, most natural version for a future/open condition is Se passares (future subjunctive).
Se passas tends to sound like you are talking about a repeated / already established pattern, and even then, many speakers still prefer Se passares.

For learners, it’s safer and more idiomatic to use:

Se
- future subjunctive (passares)
main clause in present indicative (ficas, estudas)

How would this sentence change if I wanted to speak formally to someone (using você)?

For formal você, the verb forms change to 3rd person singular, and the possessive normally becomes seu:

Se passar do seu limite de café, fica nervoso e estuda pior.

Here:

passar = future subjunctive (3rd person singular of você)
seu limite = your limit (formal “you”)
fica, estuda = present indicative (3rd person singular)

So the structure is the same, but all the verb and possessive forms shift from tu/teu to você/seu.