Na urodziny kupię babci kwiaty.

Here na urodziny means for a birthday / as a birthday gift.

In Polish, na is often used in expressions like this to mean for an occasion:

• na urodziny = for a birthday
• na święta = for Christmas / for the holidays
• na imieniny = for a name day

So this phrase does not have to mean only on the exact birthday day. Very often it means as a present for the birthday occasion.

In Polish, urodziny is normally a plural noun. That is just how the language expresses this idea.

So even when talking about one person’s birthday, Polish says:

• Mam dziś urodziny. = It’s my birthday today.
• Prezent na urodziny = a birthday present

This is similar to how some ideas are grammatically plural in one language but singular in another.

Because babci is in the dative case.

The base form is babcia = grandma.
In this sentence, grandma is the recipient of the flowers, so Polish uses the dative:

• babcia = grandma
• babci = to/for grandma

So:

• kupię babci kwiaty = I will buy grandma flowers / I will buy flowers for grandma

This is very common in Polish with verbs involving giving, showing, buying, sending, etc.

You can say dla babci, but the structure here uses the dative instead, which is very natural.

Compare:

• Kupię babci kwiaty. = I’ll buy grandma flowers.
• Kupię kwiaty dla babci. = I’ll buy flowers for grandma.

Both are correct, but they are built differently:

• babci = recipient in the dative
• dla babci = a prepositional phrase meaning for grandma

With verbs like dać, kupić, pokazać, the dative is especially common for the person receiving something.

Kwiaty is the accusative plural here, because it is the direct object of kupię.

The singular is:

• kwiat = flower

The plural is:

• kwiaty = flowers

For many non-masculine-personal nouns, the accusative plural looks the same as the nominative plural, so:

• nominative plural: kwiaty
• accusative plural: kwiaty

That is why the form does not change here.

Kupię is the 1st person singular future form of kupić.

It means:

• I will buy
• I’ll buy

A very important point: kupić is a perfective verb. That means it presents the action as a completed whole. So kupię suggests a single completed future action: I will buy.

Compare:

• kupię = I will buy
• będę kupować = I will be buying / I will buy (imperfective, focusing more on the process or repeated action)

In this sentence, kupię is the natural choice.

Because Polish often leaves out subject pronouns when they are clear from the verb form.

The ending -ę in kupię already tells you the subject is I.

So Polish usually says:

• Kupię babci kwiaty.

rather than:

• Ja kupię babci kwiaty.

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

No, Polish word order is fairly flexible.

Na urodziny kupię babci kwiaty is a natural, neutral sentence, but other orders are also possible:

• Kupię babci kwiaty na urodziny.
• Babci kupię kwiaty na urodziny.
• Kwiaty kupię babci na urodziny.

These all mean roughly the same thing, but the emphasis changes.

For example:

• Na urodziny at the beginning highlights the occasion.
• Babci earlier can highlight the person receiving the gift.
• Kwiaty earlier can highlight what will be bought.

So word order in Polish often helps show focus rather than changing the basic meaning.

Sometimes English translation can depend on context, but in a sentence like this, na urodziny most naturally means for her birthday or as a birthday gift.

If you specifically wanted to emphasize on the birthday day, Polish would more naturally use something like:

• w urodziny = on the birthday

So:

• Na urodziny kupię babci kwiaty = I’ll buy grandma flowers for her birthday.
• W urodziny kupię babci kwiaty = I’ll buy grandma flowers on her birthday.

The first one is the more standard choice for a present.

Good observation: babci can represent more than one case.

For babcia, the form babci can be:

• genitive singular
• dative singular
• locative singular

So by itself, babci is ambiguous. But in a full sentence, the grammar usually makes the function clear.

Here, after kupię, it clearly works as the dative recipient:

• kupię babci kwiaty = I’ll buy grandma flowers

So even though the form is shared by multiple cases, the sentence structure tells you which one it is.

Mainly through case endings and the verb form.

In this sentence:

• kupię tells us the subject is I
• babci tells us to/for grandma because it is dative
• kwiaty tells us the thing being bought, the direct object
• na urodziny gives the occasion/purpose

So Polish relies much more on endings than English does. English often needs word order and prepositions like for; Polish can encode the same information directly in the noun forms.