Szefowa powiedziała, że dziś nie musimy robić nadgodzin.

Szefowa means female boss, while szef means male boss or sometimes just boss in a more general sense.

In this sentence, the speaker is talking about a woman, so szefowa is used. This also affects the verb later in the sentence: powiedziała is the feminine past form, matching szefowa.

Powiedziała is the past tense, 3rd person singular, feminine form of powiedzieć (to say / to tell).

Polish past tense agrees with the gender of the subject:

• powiedział = he said
• powiedziała = she said
• powiedziało = it said

Since szefowa is feminine, the sentence uses powiedziała.

Both can relate to speaking, but they are used differently.

• powiedzieć usually means to say, often for a completed statement
• mówić usually means to speak / to be saying / to talk

Here, powiedziała works well because the idea is that the boss made a specific statement. In English, said is the most natural match.

In Polish, a comma is normally used before że when it introduces a subordinate clause.

So:

• Szefowa powiedziała, że... = The boss said that...

This is standard Polish punctuation. English sometimes omits that, but Polish normally keeps że in this kind of sentence.

Że means that.

It introduces the content of what was said:

• Szefowa powiedziała, że...
  = The boss said that...

It is a very common connector in Polish.

Yes. Dziś and dzisiaj both mean today.

• dziś is a bit shorter and slightly more compact in style
• dzisiaj is also completely normal and very common

So you could also say:

• Szefowa powiedziała, że dzisiaj nie musimy robić nadgodzin.

That would mean the same thing.

Musimy is the 1st person plural form of musieć (to have to / must).

The conjugation is:

• muszę = I have to
• musisz = you have to
• musi = he/she/it has to
• musimy = we have to
• musicie = you all have to
• muszą = they have to

So nie musimy means we do not have to.

No. This is a very important point.

• nie musimy = we don’t have to
• nie możemy = we can’t / we may not
• nie wolno nam = we are not allowed to

So this sentence means there is no obligation to work overtime today. It does not mean overtime is forbidden.

After musieć, Polish normally uses an infinitive, just like English uses to + verb or a bare verb idea like have to do.

So:

• musimy robić = we have to do / work
• musimy iść = we have to go
• musimy czekać = we have to wait

In this sentence:

• nie musimy robić nadgodzin = we don’t have to work overtime

This is because of negation.

The expression is:

• robić nadgodziny = to work overtime

But after a negated verb, Polish often changes the direct object from the accusative to the genitive:

• robimy nadgodziny = we work overtime
• nie robimy nadgodzin = we do not work overtime

So in your sentence:

• nie musimy robić nadgodzin

the noun appears in the genitive plural: nadgodzin.

This is a very common pattern in Polish grammar.

Nadgodziny means overtime hours or simply overtime.

It is usually used in the plural in Polish:

• robić nadgodziny = to work overtime
• mieć nadgodziny = to have overtime
• płacić za nadgodziny = to pay for overtime

In your sentence, the meaning is about extra work hours beyond the normal schedule.

Yes. Polish word order is more flexible than English word order.

The original sentence is completely natural:

• Szefowa powiedziała, że dziś nie musimy robić nadgodzin.

But you could also hear:

• Szefowa powiedziała, że nie musimy dziś robić nadgodzin.
• Dziś szefowa powiedziała, że nie musimy robić nadgodzin.

These versions shift the emphasis slightly, but the core meaning stays the same.

Because the boss’s statement happened in the past, but what she said is about today’s current situation.

So:

• powiedziała = she said
• musimy = we have to

This is normal in both Polish and English. Compare:

• She said that today we don’t have to work overtime.

The act of speaking is past, but the content refers to the present situation.

It is very normal, natural everyday Polish. It would sound fine in speech and in writing.

A few small variations are possible, such as using dzisiaj instead of dziś, but the sentence as written is standard and idiomatic.