Do jogurtu dodaję borówki, bo po chorobie chcę jeść więcej owoców.

In Polish, a comma is normally placed before bo when it introduces a reason clause.

So:

Do jogurtu dodaję borówki, bo po chorobie chcę jeść więcej owoców.

This works like English because in a sentence such as:

I add blueberries to yogurt, because after being ill I want to eat more fruit.

In natural English, the comma is often optional or omitted before because, but in Polish the comma is standard here.

Because do jogurtu means into the yogurt / to the yogurt, which is what you use with the verb dodawać.

The usual pattern is:

dodawać coś do czegoś = to add something to something

So:

• dodaję borówki do jogurtu = I add blueberries to yogurt

By contrast:

• w jogurcie = in the yogurt

That would describe location, not the act of adding. So borówki są w jogurcie means the blueberries are in the yogurt, but dodaję borówki do jogurtu means I am adding blueberries to the yogurt.

Jogurtu is in the genitive singular.

That is because the preposition do requires the genitive:

• do + genitive

So:

• jogurt = base form
• do jogurtu = to/into the yogurt

This is a very common pattern in Polish:

• do domu = to the house/home
• do szkoły = to school
• do kawy = to the coffee

Dodaję is the 1st person singular present tense form, meaning I add or I am adding.

It comes from the imperfective verb dodawać.

So:

• dodawać = to add, to be adding
• dodaję = I add / I’m adding

Polish present tense often covers both English simple present and present continuous, so depending on context it can mean:

• I add blueberries to yogurt
  or
• I’m adding blueberries to yogurt

Because dodaję is imperfective, and it fits a general, ongoing, or repeated action.

Here the sentence sounds like a habit or a current practice:

I add blueberries to yogurt because after being ill I want to eat more fruit.

If you used dodam, that would be from the perfective verb dodać, and it usually refers to a completed future action:

• dodam = I will add

So:

• dodaję = I add / I’m adding
• dodam = I will add

Because Polish usually drops subject pronouns when the verb already shows who is doing the action.

The ending -ę in dodaję and chcę already tells you the subject is I.

So ja is not necessary.

You could say:

Ja dodaję borówki...

but that would usually add emphasis, for example:

• I add blueberries, not someone else.

In normal speech, just dodaję is enough.

Here borówki is the accusative plural, because it is the direct object of dodaję.

You are adding what?
borówki

For many feminine plural nouns, the accusative plural looks the same as the nominative plural. That is what happens here:

• singular: borówka
• plural nominative: borówki
• plural accusative: borówki

So the form does not change, even though the case function does.

Usually borówki means blueberries, though in some contexts it can overlap with bilberries depending on region and everyday usage.

A useful rough guide is:

• borówki = blueberries
• jagody = often wild forest berries, especially bilberries in everyday Polish
• żurawina = cranberry

So for a learner, borówki is best understood here as blueberries.

Bo means because.

It is very common and natural in everyday Polish.

You could also use:

• ponieważ = because, since
• gdyż = because, more formal/written

So these are possible too:

• ...bo po chorobie chcę jeść więcej owoców.
• ...ponieważ po chorobie chcę jeść więcej owoców.

The version with bo sounds the most conversational and natural here.

Here po means after, and in this meaning it takes the locative case.

So:

• choroba = illness
• po chorobie = after the illness / after being ill

That is why the ending changes to -ie.

Be careful: po can take different cases in different meanings. For example, with motion and the meaning to fetch/get, it can take the accusative:

• idę po chleb = I’m going to get bread

But in po chorobie meaning after illness, it is locative.

Because after chcieć = to want, Polish normally uses the infinitive of the next verb.

So:

• chcę jeść = I want to eat
• chcę odpocząć = I want to rest
• chcę czytać = I want to read

This is very similar to English want to eat, except Polish uses the infinitive directly without a separate word like to.

Because więcej requires the genitive.

This is a very important Polish pattern:

• więcej + genitive

So:

• owoce = fruits
• więcej owoców = more fruit / more fruits

The same happens with other quantity words:

• dużo owoców = a lot of fruit
• mało owoców = little/not much fruit
• kilka owoców = a few fruits

So więcej owoce would be incorrect.

Because Polish often uses the plural owoce where English naturally uses the mass noun fruit.

So:

• jem dużo owoców = I eat a lot of fruit
• chcę jeść więcej owoców = I want to eat more fruit

In English, fruit is often treated as an uncountable category word. In Polish, the plural form is very normal in this kind of sentence.

No, Polish word order is fairly flexible, though some orders sound more natural than others.

The given sentence is natural:

Do jogurtu dodaję borówki, bo po chorobie chcę jeść więcej owoców.

But other versions are also possible, for example:

• Borówki dodaję do jogurtu, bo po chorobie chcę jeść więcej owoców.
• Po chorobie chcę jeść więcej owoców, więc dodaję borówki do jogurtu.

Changing the order can shift emphasis:

• Do jogurtu at the start emphasizes what you are adding them to.
• Borówki at the start emphasizes what you add.
• Po chorobie at the start emphasizes the reason/background first.

It can mean either, depending on context.

Polish present tense often covers both:

• I add
• I am adding

So dodaję could describe:

1. a habit or regular practice
   
   • I add blueberries to yogurt
2. something happening right now
   
   • I’m adding blueberries to the yogurt

In this sentence, because of po chorobie chcę jeść więcej owoców, it most naturally sounds like a current habit or a new routine after being ill.