Dziś pracuję do ósmej.

Because after the preposition do in this meaning (until / up to), Polish uses the genitive case.

So:

• osiem = eight
• ósma = eighth / the eighth hour
• do ósmej = until eight

In time expressions, Polish often uses an implied word like godzina (hour), so do ósmej really means something like until the eighth hour, which is why the form changes.

Ósmej is the genitive singular feminine form of ósma.

This happens because:

1. do requires the genitive
2. the hidden noun is feminine: godzina (hour)

So the full underlying idea is:

• do ósmej godziny or more naturally do godziny ósmej
• but in everyday Polish, godzina is usually omitted

That leaves just:

• do ósmej

So even though you do not see godzina, the adjective/ordinal still agrees with it.

Because Polish very often leaves it out when the meaning is obvious.

A native speaker understands that do ósmej means until eight o’clock, so saying godziny every time would usually sound unnecessary.

Compare:

• Pracuję do ósmej. = I work until eight.
• Pracuję do ósmej godziny. = grammatically understandable, but not the usual everyday way

This omission is very common with clock times in Polish.

Pracuję is the 1st person singular present tense form of pracować (to work).

So:

• pracuję = I work / I am working

Polish usually does not need a separate subject pronoun here, because the verb ending already shows who is doing the action.

Examples:

• pracuję = I work
• pracujesz = you work
• pracuje = he/she/it works

So in Dziś pracuję do ósmej, the -ę ending tells you the subject is I.

Because Polish often drops subject pronouns when they are not needed.

The verb form already tells you the subject:

• pracuję clearly means I work

Adding ja is possible, but it usually adds emphasis or contrast:

• Ja dziś pracuję do ósmej. = I’m the one working until eight today / As for me, I work until eight today

In neutral sentences, Polish normally just says:

• Dziś pracuję do ósmej.

Yes. Dziś and dzisiaj both mean today.

The difference is mostly stylistic:

• dziś = slightly shorter, very common
• dzisiaj = also very common, sometimes sounds a little fuller or more neutral depending on context

In most everyday situations, they are interchangeable:

• Dziś pracuję do ósmej.
• Dzisiaj pracuję do ósmej.

Both are natural.

Yes. Polish word order is more flexible than English, although some orders sound more natural depending on emphasis.

For example, all of these are possible:

• Dziś pracuję do ósmej.
• Pracuję dziś do ósmej.
• Do ósmej dziś pracuję. — possible, but more marked or unusual in normal conversation

The original sentence is natural because it starts with today, which sets the time frame right away.

A good rule:

• Polish word order often changes to reflect focus or emphasis, not basic grammatical correctness.

It means until eight.

This is an important distinction:

• do ósmej = until eight
• o ósmej = at eight

So:

• Dziś pracuję do ósmej. = Today I’m working until eight.
• Dziś pracuję o ósmej. would not mean the same thing; it would suggest something happening at eight, and with pracować that would sound odd unless the context supported it

So remember:

• do = endpoint, until
• o = specific time, at

Polish often tells time using forms related to ordinal numbers, not just cardinal numbers.

That is why you see:

• pierwsza = one o’clock
• druga = two o’clock
• ósma = eight o’clock

Then after certain prepositions, the form changes by case:

• o ósmej = at eight
• do ósmej = until eight

So Polish is not really saying just eight here. It is treating the time as the eighth hour.

A rough pronunciation guide is:

• Dziś ≈ jish (with a soft zh/sh-like sound)
• pracuję ≈ pra-TSOO-yeh
• do = doh
• ósmej ≈ OOS-may

A more detailed breakdown:

• dziś has a soft consonant sound that English does not match perfectly
• c in pracuję sounds like ts
• j in Polish sounds like English y
• ó is pronounced like u
• ej in ósmej sounds roughly like ay

So the whole sentence is approximately:

jish pra-TSOO-yeh doh OOS-may

Yes, you could, and it is grammatically correct.

• do ósmej = everyday, natural, concise
• do godziny ósmej = more explicit, sometimes more formal or deliberate

In normal speech, people usually prefer the shorter version:

• Dziś pracuję do ósmej.

But it is useful to know the full structure because it helps explain the grammar. The shorter version is basically a reduced form of the longer one.

It can mean either, depending on context.

Polish present tense often covers both:

• I work
• I am working

So Dziś pracuję do ósmej could mean:

• Today I work until eight
• Today I’m working until eight

In real usage, English would usually prefer I’m working until eight today, but Polish does not need a separate progressive form here.