Learn Hardcore Russian: Стипендия помогает ей учиться и не беспокоиться о деньгах, а по вечерам она подрабатывает поваром. - The scholarship helps her study and not worry about money, and in the evenings she has a side job as a cook.

Russian has no articles at all (no a/an or the). The bare noun стипендия can mean a scholarship, the scholarship, or just scholarship in general, depending on context.

Here Стипендия is in the nominative case and is simply the subject of the sentence: Стипендия помогает… = The scholarship helps… / A scholarship helps…. The specific English article is chosen by context, not marked in Russian.

Why is it ей after помогает, and not она or её?

The verb помогать / помочь (to help) takes the dative case for the person who receives the help:

помогать кому? – to help whom? (dative)

Она is nominative (she – subject),
её is genitive or accusative (her / of her),
ей is dative (to her).

So we need ей:

Стипендия помогает ей… = The scholarship helps her…

Why is учиться used, and not учить?

Учить and учиться are different verbs:

учить кого? что? – to teach / to learn something (transitive)
- учить математику – to study/learn mathematics
- учить детей – to teach children
учиться (где? как? чему?) – to study, to be engaged in studying (in general or at an institution)
- учиться в университете – to study at university
- ей нужно учиться – she needs to study

In your sentence, we are not specifying a subject being studied; we are talking about her general activity of studying. That’s why учиться (reflexive form) is used:

…помогает ей учиться… = …helps her to study… (in general).

Why is не беспокоиться also in the infinitive after помогает?

Помогает can be followed by an infinitive that expresses what the help allows someone to do:

помогает ей учиться – helps her to study
помогает ей не беспокоиться – helps her not to worry

When there is a list of actions with the same subject after one verb, Russian usually:

Says the first infinitive: учиться
Then just adds another infinitive in the same form: и не беспокоиться

So we get:

помогает ей учиться и не беспокоиться…
= helps her (to) study and (to) not worry…

Both infinitives share the same subject (она) and depend on помогает.

What is the function of не in не беспокоиться here?

Не is just the normal particle for negation in Russian; it directly negates the verb:

беспокоиться – to worry, to be anxious
не беспокоиться – not to worry

English uses not before the infinitive (not to worry); Russian attaches не directly to the verb: не беспокоиться.

What does the -ся / -сь ending in учиться and беспокоиться mean?

The -ся / -сь ending marks a reflexive or “middle-voice” verb. It often makes the verb mean:

“do something to oneself”
“be in a certain state”
“perform the action without a direct object”

In your verbs:

учить – to teach / to learn something (transitive)
учиться – to study (be engaged in learning; no direct object)
беспокоить – to worry / disturb someone
беспокоиться – to worry, to be anxious (about something oneself)

So учиться and беспокоиться describe her own activity or state, not an action directed at someone else.

Why is it о деньгах and not something like о деньги or о денег?

The preposition о (about) takes the prepositional case:

о ком? о чём? – about whom? about what?

The noun деньги (money) is plural-only. Its prepositional plural form is о деньгах.

Declension of деньги (only the main forms):

Nom. plural: деньги – money
Gen. plural: денег – of money
Dat. plural: деньгам – to money
Acc. plural: деньги – money (object)
Instr. plural: деньгами – with money
Prep. plural: о деньгах – about money

So о деньгах literally = about (the) money.

What does а mean in …о деньгах, а по вечерам…? Why not just и?

Both и and а can be translated as and, but they have different roles:

и = and, simply adds information, joins similar items.
а = and / but, often shows contrast, shift, or different aspect of the same situation.

In your sentence:

Стипендия помогает ей учиться… – one side of her life (financial support).
а по вечерам она подрабатывает… – another side, contrasted: despite the scholarship, she also works in the evenings.

So а here is like “and (at the same time / but also)”, signaling a change of focus or a slight contrast. That’s why there is a comma before а: it connects two clauses.

What does по вечерам mean exactly, and why по?

По вечерам literally means on (the) evenings, but idiomatically:

по вечерам = in the evenings / in the evenings (regularly, habitually)

Structure:

по
- dative plural:
  - вечер (evening) → dative plural вечерам
  - по вечерам – on evenings

Russian uses по + dative plural to express repeated time periods:

по утрам – in the mornings
по выходным – on weekends
по ночам – at night(s)

So по вечерам suggests something she regularly does in the evenings, not just once.

What is the exact meaning of подрабатывает? How is it different from just работает?

Работать – to work (in general).
Подрабатывать – to earn extra money on the side, to have a side job / part-time job in addition to a main activity.

Nuance:

Она работает поваром. – She works as a cook (that’s her main job).
Она подрабатывает поваром. – She works part-time / on the side as a cook, usually in addition to something else (here: her studies).

So подрабатывать emphasizes the extra, supplementary nature of the work, often to support oneself financially.

Why is поваром in that form, with -ом, and no preposition? Why not как повар?

Поваром is the instrumental case of повар (cook). Professions after verbs like быть, работать, подрабатывать, etc., are usually put in the instrumental:

работать кем? – work as who / what?
подрабатывать кем? – moonlight / earn extra as who / what?

Examples:

Он работает врачом. – He works as a doctor.
Она подрабатывает репетитором. – She has a side job as a tutor.

Thus:

подрабатывать поваром = to work (part-time) as a cook

You can say как повар in Russian, but that usually means “as a cook, in the capacity of a cook” in some specific situation and is less standard for job description than just instrumental alone after these verbs.

Can the word order be changed, for example: Она по вечерам подрабатывает поваром? Is that still correct?

Yes, Russian has relatively flexible word order. All of these are grammatical:

По вечерам она подрабатывает поваром.
Она по вечерам подрабатывает поваром.
Она подрабатывает поваром по вечерам.

They all mean roughly the same: She works part-time as a cook in the evenings.

The difference is in emphasis:

По вечерам она подрабатывает… – emphasizes the evenings (when she works).
Она по вечерам подрабатывает… – more neutral; subject first, then time.
Она подрабатывает поваром по вечерам. – slightly highlights the fact that she works as a cook, time is added after.

In your original sentence, starting the clause with по вечерам sets the time frame as important new information.

Why are all the verbs here imperfective (помогает, учиться, не беспокоиться, подрабатывает)?

Imperfective aspect in Russian is used for:

ongoing, habitual, repeated actions
states or general facts

In the sentence:

Стипендия помогает ей… – the scholarship regularly / generally helps her.
…учиться и не беспокоиться… – she is able to study and not worry as a continuing situation.
…она подрабатывает поваром. – she regularly works part-time as a cook in the evenings.

Since we’re describing her typical, ongoing life situation, imperfective is the natural choice. A perfective form would suggest a single, completed event, which is not what is meant here.