W naszym wieku wiele osób już pracuje na etat, ale ona jeszcze uczy się na uczelni.

Because after w meaning in / at in a static sense, Polish normally uses the locative case.

• wiek = age
• locative singular of wiek = wieku
• nasz has to match it, so you get naszym

So:

• w wieku = at the age / in the age
• w naszym wieku = at our age

This is a very common idiomatic phrase meaning when people are our age or at our stage of life.

No. It does not automatically mean old age.

w naszym wieku simply means at our age or when someone is as old as we are. The actual age depends entirely on context.

For example, it could be said by:

• teenagers,
• university students,
• middle-aged people,
• elderly people.

So the phrase itself is neutral; it just compares people in the same age group.

Because wiele behaves like a quantity word and requires the genitive plural.

• basic singular: osoba = person
• nominative plural: osoby = people
• genitive plural: osób

After wiele you use the genitive plural:

• wiele osób = many people

This is similar to other quantity expressions in Polish:

• dużo osób = a lot of people
• kilka osób = a few people
• mało osób = few people

So wiele osoby is incorrect.

This is one of the things that feels strange to English speakers.

In Polish, expressions like wiele osób often take a singular verb form, especially in standard grammar.

So:

• Wiele osób pracuje. = Many people work.

Even though the meaning is plural, grammatically the construction is treated differently from a simple plural noun like osoby pracują.

Compare:

• Osoby pracują. = The people are working.
• Wiele osób pracuje. = Many people work.

In the past tense, this becomes even more noticeable:

• Wiele osób pracowało.

That singular agreement is normal here.

już here means already.

So:

• wiele osób już pracuje na etat = many people already have regular jobs / are already working full-time

It suggests that this is something that has happened earlier than expected, or that it is now true when maybe it was not true before.

Very often, już contrasts nicely with jeszcze:

• już = already
• jeszcze = still / yet

And that is exactly what happens in this sentence.

Here it means still.

• ona jeszcze uczy się na uczelni = she is still studying at university/college

In other contexts, jeszcze can also mean yet, but in this sentence the idea is clearly still: other people already work, but she continues to study.

So the contrast is:

• już pracuje = already works
• jeszcze uczy się = is still studying

Because the verb for to learn / to study is uczyć się.

Without się, uczyć usually means to teach:

• uczyć kogoś = to teach someone

With się, it means to learn / to study:

• uczyć się = to learn, to study

So:

• ona uczy się = she studies / she is learning

For an English speaker, this is important because Polish often distinguishes these meanings through się.

Compare:

• Nauczyciel uczy studentów. = The teacher teaches the students.
• Studenci uczą się. = The students study / are learning.

Because się is a clitic-like little word in Polish, and it usually comes after the verb or later in the clause, not at the very beginning.

So:

• uczy się = normal
• się uczy = possible in some contexts for emphasis, but not the neutral default

In this sentence, uczy się is the most natural order.

You will often see się in slightly different positions depending on rhythm, emphasis, and style, but uczy się is the standard pattern learners should start with.

pracować na etat is an idiomatic expression meaning something like:

• to work in a regular salaried position
• to have a proper employee job
• often, in practice, to work full-time

The noun etat means a job post/position, and in everyday speech na etat often suggests stable, standard employment rather than casual or temporary work.

A useful nuance:

• na etat often implies regular employment
• na pełny etat = full-time
• na pół etatu = half-time / part-time

So na etat is not just a literal word-for-word phrase; it is a set expression.

Here na means at/on in the sense of location, so it takes the locative case.

• dictionary form: uczelnia
• locative singular: uczelni

So:

• na uczelni = at a university / at college / in higher education

This use of na is common with institutions and places:

• na uniwersytecie = at the university
• na poczcie = at the post office
• na uczelni = at college/university

If na indicated movement toward something, you would usually expect the accusative instead, but here it is a location, so locative is correct.

uczelnia is a broader word.

• uczelnia = higher-education institution
• uniwersytet = university

So uczelnia can refer to:

• a university,
• a technical university,
• an academy,
• another kind of higher-education school.

That means na uczelni is slightly more general than na uniwersytecie.

In this sentence, na uczelni fits well because it simply says she is still in higher education, without specifying the exact kind of institution.

Yes, Polish could omit it.

A version without the pronoun would be:

• W naszym wieku wiele osób już pracuje na etat, ale jeszcze uczy się na uczelni.

However, that sounds less clear because after ale the listener may want an explicit subject. Including ona makes the contrast stronger and clearer:

• many people already work, but she still studies

In Polish, subject pronouns are often omitted because the verb ending already shows the person. But they are commonly included for:

• contrast
• emphasis
• clarity

Here ona is contrastive: other people do one thing, she does another.

The word order is fairly natural, but Polish word order is more flexible than English.

The sentence has:

• ale ona jeszcze uczy się na uczelni

This highlights jeszcze before the verb phrase, which nicely brings out the meaning still.

Other orders may be possible, for example:

• ale ona uczy się jeszcze na uczelni

That can also work, but it may sound slightly different in emphasis. The given version is very natural because it sets up the contrast cleanly:

• others already work,
• she still studies.

So the order is not absolutely fixed, but it is well chosen.

Not necessarily right this second. In Polish, the present tense often describes a current general situation or ongoing stage of life.

So:

• pracuje = works / is working
• uczy się = studies / is studying

Here the meaning is not that one group is literally working at this exact moment and she is literally sitting in class at this exact moment. Instead, it describes their present life situation:

• many people of that age already have regular jobs,
• but she is still a student.

So the present tense is completely natural.

Yes.

Polish present tense often corresponds to both:

• English simple present
• English present continuous

depending on context.

So uczy się na uczelni can mean:

• she studies at university
• she is studying at university

In this sentence, English would probably prefer she is still studying at university, because it fits the contrast with already working very naturally.