W sklepie terminal nie działał, więc kobieta przede mną musiała zapłacić gotówką.

Because after w meaning in, Polish normally uses the locative case.

• sklep = shop/store
• w sklepie = in the shop/store

So:

• w domu = in the house
• w pracy = at work
• w sklepie = in the shop

Be careful: w can also take the accusative when it means motion into somewhere:

• Idę w sklep — this is not natural Polish
• Idę do sklepu = I’m going to the shop
• Wchodzę w coś = I’m going into something / entering into something

For places like shop, Polish usually says do sklepu for to the shop, but w sklepie for in the shop.

działać means to work / function / operate.

So:

• terminal działał = the terminal was working
• terminal nie działał = the terminal was not working

The form działał is:

• past tense
• masculine singular
• matching terminal, which is a masculine noun

That is why it is not działała or działało.

Examples:

• Telefon nie działał. = The phone wasn’t working.
• Maszyna nie działała. = The machine wasn’t working.
  (maszyna is feminine, so działała)
• Urządzenie nie działało. = The device wasn’t working.
  (urządzenie is neuter, so działało)

Polish does not have articles like a, an, or the.

So:

• terminal can mean a terminal or the terminal
• kobieta can mean a woman or the woman

You understand which one is meant from context.

In this sentence:

• terminal nie działał = the terminal wasn’t working
• kobieta przede mną = the woman in front of me

English needs articles, but Polish does not.

więc means so, therefore, or thus.

It connects the two parts of the sentence:

• W sklepie terminal nie działał = In the shop, the terminal wasn’t working
• więc kobieta przede mną musiała zapłacić gotówką = so the woman in front of me had to pay in cash

It is a very common way to show result or consequence.

Compare:

• Padało, więc zostałem w domu. = It was raining, so I stayed home.
• Nie miał czasu, więc nie przyszedł. = He didn’t have time, so he didn’t come.

Because przede mną means in front of me, and after the preposition przed/przede, Polish uses the instrumental case in this meaning.

The pronoun ja changes in the instrumental:

• ja = I
• mną = me (after certain prepositions/instrumental)

So:

• przede mną = in front of me
• za mną = behind me
• nade mną = above me

Why przede instead of just przed?
It is mainly for pronunciation. Polish sometimes adds an extra vowel in front of certain pronouns or clusters:

• przede mną
• nade mną
• ze mną

These are standard forms.

Because it is the past tense feminine singular form of musieć = to have to / must.

The subject is kobieta (woman), which is feminine, so the verb must agree with it:

• musiał = he had to
• musiała = she had to
• musiało = it had to (neuter)

So:

• kobieta musiała = the woman had to
• mężczyzna musiał = the man had to
• dziecko musiało = the child had to

In Polish past tense, verbs often show the gender of the subject.

Because after musieć, Polish uses the infinitive.

So the pattern is:

• musieć + infinitive
• musiała zapłacić = she had to pay

Compare:

• Muszę iść. = I have to go.
• Musieliśmy czekać. = We had to wait.
• Ona musiała zapłacić. = She had to pay.

If you said zapłaciła, that would be a separate past-tense verb meaning she paid, not an infinitive.

So:

• musiała zapłacić = she had to pay
• zapłaciła = she paid

Because zapłacić gotówką uses the instrumental case.

• gotówka = cash
• gotówką = with cash / in cash

In Polish, the instrumental is often used for the means or method of doing something.

So:

• zapłacić gotówką = pay in cash
• zapłacić kartą = pay by card
• jechać autobusem = go by bus
• pisać długopisem = write with a pen

This is a very common pattern.

Grammatically, yes, but it would sound less natural here.

• gotówka specifically means cash
• pieniądze means money in a broader sense

Since the sentence contrasts a non-working card terminal with another payment method, gotówką is the natural choice.

So:

• zapłacić gotówką = pay in cash
• zapłacić kartą = pay by card

That contrast is exactly what the sentence is about.

Yes, Polish word order is quite flexible, but the version here sounds natural and clear.

Current order:

• W sklepie = in the shop
• terminal nie działał = the terminal wasn’t working
• więc kobieta przede mną musiała zapłacić gotówką = so the woman in front of me had to pay in cash

You could also say:

• Terminal w sklepie nie działał, więc kobieta przede mną musiała zapłacić gotówką.

That slightly shifts focus toward the terminal.

Or:

• Kobieta przede mną musiała zapłacić gotówką, bo w sklepie terminal nie działał.

That changes the structure a bit by using bo = because instead of więc = so.

So yes, word order can change, but the original sentence is a very natural way to say it.

They are related, but not the same.

• więc = so
• bo = because

In your sentence:

• Terminal nie działał, więc kobieta musiała zapłacić gotówką.
  = The terminal wasn’t working, so the woman had to pay in cash.

If you use bo, you reverse the logic:

• Kobieta musiała zapłacić gotówką, bo terminal nie działał.
  = The woman had to pay in cash because the terminal wasn’t working.

So:

• X, więc Y = X, so Y
• Y, bo X = Y, because X

Yes. In everyday Polish, terminal commonly means a payment terminal or card terminal in a shop.

So:

• terminal nie działał = the card terminal wasn’t working

If needed, someone could say terminal płatniczy for extra clarity, but in normal conversation terminal is usually enough.

Examples:

• Mogę zapłacić kartą?
• Nie, terminal nie działa.
  = Can I pay by card?
  = No, the terminal isn’t working.

Here, kobieta przede mną clearly means the woman ahead of me / in front of me, for example in a queue.

Literally:

• przed = before / in front of
• przede mną = before me / in front of me

Depending on context, przed can refer to:

1. space

   • Stał przede mną. = He was standing in front of me.

2. time

   • To było przede mną. = That was before me.
     This is less common in this exact phrasing, but possible in some contexts.

In a shop situation, the meaning is clearly spatial: the woman was ahead of the speaker, probably in line.

A natural present-tense version would be:

• W sklepie terminal nie działa, więc kobieta przede mną musi zapłacić gotówką.

Changes:

• działał → działa
• musiała → musi

So:

• nie działa = isn’t working
• musi zapłacić = has to pay

The rest stays the same.

It describes a specific past situation.

Clues:

• działał = was working / worked
• musiała = had to

These past-tense forms suggest a concrete event: the speaker was in a shop, the terminal was not working at that time, and a woman ahead of them had to pay cash.

It is not a general rule like:

• W tym sklepie terminal często nie działa. = In this shop, the terminal often doesn’t work.

Instead, it sounds like one episode the speaker is recounting.