W sobotę w centrum jest wyprzedaż, więc chcę kupić nowe kolczyki i bransoletkę.

Because in Polish, w can take different cases depending on meaning.

• For location, w usually takes the locative:
  
  • w domu = in the house
  • w centrum = in the center
• But for time expressions like on Saturday, Polish uses w + accusative:
  
  • w sobotę = on Saturday
  • w niedzielę = on Sunday

So w sobotę is a standard time expression meaning on Saturday.

Centrum is one of those nouns whose singular form usually does not change in spelling across the cases.

So even though w for location requires the locative, the form still looks the same:

• centrum = center
• w centrum = in the center

Grammatically it is locative, but visually it looks unchanged.

Literally, it is something like there is a sale.

In Polish, jest often works like there is / there exists in English.

• jest wyprzedaż = there is a sale
• jest problem = there is a problem

So the sentence is not saying the sale is, but rather there is a sale happening.

Wyprzedaż means sale, often in the sense of a clearance sale or discount sale in shops.

It is commonly used when stores are selling things at reduced prices.

Related words:

• przecena = price reduction / markdown
• zniżka = discount
• wyprzedawać = to sell off

So jest wyprzedaż suggests a shopping event, not just one discounted item.

Because więc means so / therefore, and in Polish it normally introduces another clause after a comma.

Here the structure is:

• W sobotę w centrum jest wyprzedaż = On Saturday there is a sale in the center
• więc chcę kupić... = so I want to buy...

The comma helps separate the cause and result.

Yes, więc is very common. It means so, therefore, or thus.

Examples:

• Jest zimno, więc biorę kurtkę. = It’s cold, so I’m taking a jacket.
• Nie mam czasu, więc wychodzę. = I don’t have time, so I’m leaving.

It is a very useful everyday connector.

This is about aspect, which is very important in Polish verbs.

• kupić = perfective = to buy, as a completed action
• kupować = imperfective = to be buying / to buy repeatedly / to buy in general

In this sentence, the speaker wants to make a specific purchase, so kupić fits better:

• chcę kupić = I want to buy
• chcę kupować would sound more like I want to be buying / I want to buy regularly

So chcę kupić is the natural choice here.

Because nowe has to agree with kolczyki.

• kolczyki = earrings
• It is plural
• In this sentence it is the direct object

For non-masculine-personal plurals in Polish, the accusative plural usually looks the same as the nominative plural, so:

• nowe kolczyki = new earrings

That is why you see nowe, not nowych or nową.

Because bransoletka is a feminine noun, and here it is the direct object of kupić.

For many feminine nouns ending in -a, the accusative singular changes to -ę:

• bransoletka = bracelet
• kupić bransoletkę = to buy a bracelet

The same pattern appears in many common nouns:

• książka → czytam książkę
• kawa → piję kawę

As written, nowe clearly agrees only with kolczyki.

So the sentence means:

• new earrings and a bracelet

not necessarily:

• new earrings and a new bracelet

If you want new to describe both items, Polish usually repeats the adjective:

• chcę kupić nowe kolczyki i nową bransoletkę

That repetition is very natural in Polish.

Yes, the singular exists:

• kolczyk = one earring
• kolczyki = earrings

But people very often buy or talk about earrings as a pair, so the plural is common and natural.

If you wanted just one earring, you could say:

• chcę kupić nowy kolczyk = I want to buy a new earring

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

This sentence is natural as:

• W sobotę w centrum jest wyprzedaż, więc chcę kupić nowe kolczyki i bransoletkę.

But you could also rearrange parts for emphasis, for example:

• W centrum w sobotę jest wyprzedaż...
• Więc chcę kupić nowe kolczyki i bransoletkę.

The original version sounds natural and neutral, with w sobotę emphasized early.

In everyday usage, w centrum often means in the city center / downtown.

So in this sentence, a natural English interpretation is:

• in the city center
• or simply downtown

Literally it is in the center, but in context it usually refers to the central part of town.

The letter ę is a nasal vowel, but in everyday speech its pronunciation can be reduced depending on position.

Very roughly:

• chcę sounds close to h-tsen or h-tseh(n)
• sobotę sounds roughly like so-bo-teh(n)

A few useful points:

• ch sounds like a hard h
• cz sounds like ch in chop
• final ę is often pronounced less strongly than learners expect

So don’t worry if you do not produce a very strong nasal sound at first.