Lubię smażone pieczarki.

Lubię means I like. It comes from the infinitive lubić.

The ending -ę shows 1st person singular in the present tense, so the verb itself already tells you the subject is I.

Polish often leaves out subject pronouns when they are obvious from the verb ending.

So:

• Lubię smażone pieczarki. = I like fried mushrooms.
• Ja lubię smażone pieczarki. also works, but ja adds emphasis, as if you were saying I like fried mushrooms.

Pieczarki is the plural of pieczarka.

It usually means button mushrooms or champignons, not mushrooms in the broadest possible sense. The more general word for mushrooms is grzyby.

So this sentence is specifically about pieczarki, not necessarily all kinds of mushrooms.

It is in the accusative plural, because lubić normally takes a direct object in the accusative.

So in Lubię smażone pieczarki, the thing being liked is smażone pieczarki, and that object goes into the accusative.

Because for this type of noun, the accusative plural and nominative plural are the same.

Pieczarki belongs to the non-masculine-personal plural group, and in that group:

• nominative plural: pieczarki
• accusative plural: pieczarki

So even though the case changes grammatically, the form does not change visibly here.

Because smażone has to agree with pieczarki.

In Polish, adjective-like words must match the noun in:

• number
• gender/group
• case

Here pieczarki is:

• plural
• non-masculine-personal
• accusative

So the matching form is smażone.

Compare:

• smażona pieczarka = a fried mushroom
• lubię smażoną pieczarkę = I like a fried mushroom
• smażone pieczarki = fried mushrooms

It is best understood as an adjective-like participle from smażyć = to fry.

In everyday learning, it is perfectly fine to think of it simply as an adjective meaning fried.

So:

• smażyć = to fry
• smażony / smażona / smażone = fried

Yes. You could say:

• Lubię smażoną pieczarkę.

That is grammatically correct, but it usually sounds like you mean one fried mushroom.

If you are talking about food in general, the plural Lubię smażone pieczarki is more natural.

Yes, but the emphasis changes.

The most neutral version is:

• Lubię smażone pieczarki.

Other orders are possible, for example:

• Smażone pieczarki lubię.
  This emphasizes fried mushrooms.

• Lubię pieczarki smażone.
  This is possible, but it sounds less neutral and can feel contrastive, as if distinguishing them from mushrooms prepared another way.

In normal speech, putting smażone before pieczarki is the most standard choice.

Because Polish does not have articles.

So Lubię smażone pieczarki can mean things like:

• I like fried mushrooms
• I like the fried mushrooms
• I like some fried mushrooms

The exact meaning depends on context.

Usually it means a general preference.

So Lubię smażone pieczarki means I like fried mushrooms in general, not I am liking fried mushrooms right now.

Polish does not use a special continuous form here the way English sometimes contrasts I like and I am liking.

A rough English-friendly pronunciation is:

loo-BYEH sma-ZHO-neh pye-CHAR-kee

A few helpful details:

• lu sounds like loo
• bię sounds roughly like byeh
• ż sounds like the s in measure
• cz sounds like ch in church
• pie sounds roughly like pye

Stress in Polish usually falls on the second-to-last syllable, so here you get:

• luBIĘ
• smaŻOne
• pieCZARki