Bawełna jest czysta.

Bawełna is feminine.

A big clue is the ending -a. In Polish, many nouns ending in -a are feminine. Here it is also singular and in the nominative case, because it is the subject of the sentence.

Because Polish adjectives must agree with the noun they describe in gender, number, and case.

Since bawełna is feminine singular nominative, the adjective also has to be feminine singular nominative:

• masculine: czysty
• feminine: czysta
• neuter: czyste

So bawełna jest czysta is the correct agreement.

Jest means is. It is the 3rd person singular form of the verb być (to be).

So the sentence structure is:

• Bawełna = subject
• jest = is
• czysta = clean / pure

This is a normal Polish way to build a sentence with to be in the present tense.

In a normal, neutral sentence, no: you usually keep jest.

• normal sentence: Bawełna jest czysta.

If you drop it, the result may sound like a label, heading, note, or poetic style rather than a standard full sentence.

For example:

• Czysta bawełna often works as a product description: pure cotton
• but Bawełna jest czysta is a complete statement

Both are in the nominative singular here.

• bawełna is nominative because it is the subject
• czysta is nominative because predicate adjectives after jest normally stay in the nominative in Polish

So this is a good example of a subject plus a predicate adjective.

Because with an adjective after jest, Polish normally uses the nominative, not the instrumental.

So you say:

• Bawełna jest czysta.

not:

• Bawełna jest czystą.

A useful comparison:

• with a noun, Polish often uses instrumental after być
  
  • Ona jest nauczycielką. = She is a teacher.
• with an adjective, Polish uses nominative
  
  • Ona jest miła. = She is nice.

It can mean clean or pure, depending on context.

For example:

• in a laundry or dirt context, czysta usually means clean
• in a materials or composition context, it can mean pure

That is why czysta bawełna often means pure cotton or 100% cotton.

So the exact nuance depends on the situation.

Yes, it is grammatical and natural as a full statement.

However, the most natural phrasing depends on context:

• If you are making a statement about the cotton, Bawełna jest czysta is fine.
• If you mean a clothing label or material description, Polish more often uses:
  • czysta bawełna
  • 100% bawełna

So the sentence is correct, but real-life usage may vary by situation.

Yes, Polish word order is more flexible than English, but the neutral order here is:

• Bawełna jest czysta.

Other orders are possible, but they sound more marked, emphatic, or literary. For example:

• Czysta jest bawełna. — unusual, emphatic
• Jest czysta bawełna. — usually not the best choice for this meaning

For learners, the standard order is the safest one.

A rough English-style pronunciation is:

bah-VEHW-na yest CHIS-tah

A few important sounds:

• ł sounds like English w
• j sounds like English y
• cz sounds like ch, but harder and more retroflex than in English
• y in czysta is not exactly English ee or ih; it is a distinct Polish vowel

Stress in Polish usually falls on the second-to-last syllable:

• baWEŁna
• jest CZYSta

Because Polish has no articles.

So bawełna can mean things like:

• cotton
• the cotton

The exact meaning depends on context, not on a separate word like the or a.

That is very normal in Polish, and learners have to get used to understanding definiteness from the situation rather than from an article.