O relógio da sala marca cada minuto, e eu conto os minutos até o almoço.

Because de + a contracts to da in Portuguese.

• de = of / from
• a = the (feminine singular)
• de + a = da

So:

• o relógio da sala = the clock of the room = the room’s clock / the clock in the room

This kind of contraction is very common:

• de + o = do
• de + a = da
• de + os = dos
• de + as = das

In Portuguese, cada is normally followed by a singular noun.

So:

• cada minuto = each minute / every minute
• not cada minutos

This is similar to English, where we also say each minute, not each minutes.

Examples:

• cada dia = each day
• cada pessoa = each person
• cada casa = each house

Here marca comes from the verb marcar, and in this sentence it means something like:

• marks
• registers
• shows
• sometimes even ticks off

With a clock, marcar can be used to talk about what time it shows or how it marks the passing of time.

So O relógio da sala marca cada minuto suggests that the clock is marking the passage of every minute.

Yes, it could.

Portuguese often drops subject pronouns when the verb already makes the subject clear. So both of these are natural:

• eu conto os minutos
• conto os minutos

The pronoun eu may be included for:

• emphasis
• contrast
• clarity
• rhythm/style

In this sentence, eu helps highlight the contrast between the clock and the speaker:

• The clock marks the minutes, and I count them.

Because contar os minutos is the natural way to say to count the minutes.

The article os makes minutos specific: these are the minutes leading up to lunch.

Compare:

• conto os minutos = I count the minutes
• conto minutos = less natural here; it sounds more abstract or incomplete

Portuguese uses definite articles more often than English does, especially when referring to something understood in context.

It can be literal, but it also has a common emotional sense.

Literally:

• contar os minutos = to count the minutes one by one

Idiomatic feeling:

• to wait impatiently
• to watch time pass slowly
• to be eager for something

So in this sentence, eu conto os minutos até o almoço suggests:

• the speaker is waiting for lunch
• the wait feels noticeable
• they may be hungry, bored, or impatient

In Brazilian Portuguese, it is very common to use the definite article with meals in many contexts, especially when referring to a specific expected meal.

So:

• até o almoço = until lunch / until lunchtime

This sounds natural because it refers to the upcoming lunch in the situation.

You may sometimes hear meal words without an article in other contexts, but here até o almoço is the most natural phrasing.

Examples:

• antes do almoço = before lunch
• depois do jantar = after dinner
• na hora do café da manhã = at breakfast time

The comma separates two full clauses:

• O relógio da sala marca cada minuto
• eu conto os minutos até o almoço

Both parts have their own verb:

• marca
• conto

In Portuguese, a comma before e is possible when it helps separate longer clauses or improve rhythm and clarity. It is not always required before e, but here it sounds natural and helps the sentence breathe a little.

They are similar, but not exactly the same in feel.

• cada minuto = each minute / every single minute
  
  • emphasizes one by one
• todos os minutos = every minute / all the minutes
  
  • emphasizes the whole set or repeated frequency

In this sentence, marca cada minuto feels very precise and step-by-step, which fits the image of a clock marking time.

Compare:

• O relógio marca cada minuto. = The clock marks each minute.
• O relógio toca todos os minutos. = The clock chimes every minute.

Portuguese usually expresses this kind of relationship with noun + de + noun.

So:

• o relógio da sala = the clock of the room = the room’s clock / the clock in the room

This is much more natural in Portuguese than trying to stack nouns the way English sometimes does.

Other examples:

• a porta da cozinha = the kitchen door
• o livro do professor = the teacher’s book
• a janela do quarto = the bedroom window

A very close breakdown is:

• O relógio da sala = the clock of the room
• marca cada minuto = marks each minute
• e eu conto os minutos = and I count the minutes
• até o almoço = until lunch

So the structure is quite close to English overall. The biggest differences are:

• Portuguese uses da sala where English often prefers room clock or clock in the room
• Portuguese often keeps the article in expressions like o almoço

The two verbs are:

• marca ← from marcar
• conto ← from contar

Both are in the present indicative.

Conjugation:

marcar

• eu marco
• você/ele/ela marca

contar

• eu conto
• você/ele/ela conta

So in the sentence:

• O relógio ... marca because o relógio is third person singular
• eu conto because the subject is eu

Yes, relógio is masculine, and that matches its article:

• o relógio

The ending -o often suggests a masculine noun, though there are exceptions in Portuguese. In this case, the pattern works normally.

You can see the masculine agreement in:

• o relógio
• do relógio
• um relógio

The plural is:

• os relógios = the clocks

Relógio is pronounced approximately like heh-LOH-zhyoo in Brazilian Portuguese, though pronunciation varies by region.

The acute accent in relógio shows the stressed syllable:

• re-ló-gio

So the stress falls on ló.

That accent is important because Portuguese stress is not always predictable just from spelling. Without the accent, a learner might guess the stress incorrectly.