To przetarcie jest małe.

Here, to is the neuter singular demonstrative, so it means this.

It matches the noun przetarcie, which is neuter:

• ten for masculine nouns
• ta for feminine nouns
• to for neuter nouns

So:

• to przetarcie = this abrasion / this worn spot / this scuff

It is not just a filler word here.

Because przetarcie is grammatically neuter. One clue is its ending: nouns ending in -e are very often neuter in Polish.

That matters because other words in the sentence have to agree with it:

• to is neuter singular
• małe is neuter singular

So the whole sentence is built around the fact that przetarcie is neuter.

Because adjectives must agree with the noun in gender and number.

Since przetarcie is:

• singular
• neuter

the adjective must also be:

• singular
• neuter

That gives małe.

Compare:

• ten ślad jest mały — masculine
• ta rysa jest mała — feminine
• to przetarcie jest małe — neuter

Yes, in a normal present-tense sentence like this, jest is standard and expected.

So:

• To przetarcie jest małe is normal.
• To przetarcie małe sounds incomplete or very unnatural in ordinary speech.

Polish often allows flexible wording, but the present-tense form of być is usually kept in sentences like this when an adjective is the predicate.

It is in the nominative case, because it is the subject of the sentence.

You can think of the structure as:

• To przetarcie — the thing being talked about
• jest małe — what is being said about it

The adjective małe also agrees with the subject, so it is nominative singular neuter as well.

Yes, that is grammatical.

The difference is:

• To przetarcie jest małe = This abrasion is small / a specific abrasion
• Przetarcie jest małe = The abrasion is small or An abrasion is small, depending on context

Using to makes it more definite and more pointing-like: this one.

Because Polish does not have articles like English a/an and the.

Instead, Polish uses:

• context
• word order
• demonstratives such as ten / ta / to

So in this sentence:

• to means this
• it is not an article
• Polish does not need a separate word for the

That is why English speakers often feel something is missing at first, but in Polish nothing is missing.

Polish word order is fairly flexible, but the version you have is the most neutral and straightforward:

• To przetarcie jest małe.

You can change the order for emphasis, but then the sentence sounds more marked or literary.

For a learner, it is best to keep this basic order:

• demonstrative + noun
• jest
• adjective

So this sentence is a very good default pattern to copy.

They are similar, but the structure is different.

To przetarcie jest małe

• to przetarcie = this abrasion
• whole sentence = This abrasion is small

To jest małe przetarcie

• to = this / it
• małe przetarcie = a small abrasion
• whole sentence = This is a small abrasion or It is a small abrasion

So the first sentence talks about a specific abrasion and describes its size. The second sentence identifies what something is.

You would say:

• Te przetarcia są małe.

Changes:

• to → te
• przetarcie → przetarcia
• jest → są
• małe stays małe in this plural pattern

So:

• singular: To przetarcie jest małe.
• plural: Te przetarcia są małe.

Yes, it comes from the verb przetrzeć or related rubbing/wearing-through ideas, and it refers to a place that has been rubbed, worn, or scuffed.

That kind of noun formation is common in Polish: a verb can produce a noun naming:

• the action
• the result
• the mark or effect

So even if you already know the meaning, it is useful to notice that przetarcie is one of many Polish nouns built from a verbal idea. That can help you recognize similar words later.