Learn Hardcore Russian: Ей придётся остаться на работе дольше, чем обычно. - She will have to stay at work longer than usual.

Мне надо идти. – I need to go. (literally: To me it-is-necessary to go.)
Тебе придётся подождать. – You will have to wait. (literally: To you will‑be‑necessary to wait.)

So you use the dative (кому? – to whom?) to show who has the obligation:
ей придётся = she will have to (literally to her it will be necessary), not она придётся.

What exactly does придётся mean, and what form is it?

Придётся is the future tense, 3rd person singular, impersonal form of the verb прийтись.

прийтись (perfective, reflexive) – literally to befall, to come to be needed, but in practice it functions like “to have to / must (in the future)” in such constructions.

When used impersonally with a dative pronoun, it expresses a forced necessity:

Ей придётся остаться… – She will have to stay… (not her choice; circumstances force it)
Нам придётся уехать. – We will have to leave.

So придётся combines the idea of future and obligation due to circumstances. It’s less direct/authoritative than должна (must, is obliged to) and often suggests “no other choice” because of the situation.

Why does придётся end with -ся? Is it a reflexive verb here?

Yes, придётся comes from a reflexive verb прийтись (ending in -сь / -ся).

However, here -ся does not mean reflexive in the “do something to oneself” sense (like wash oneself, dress oneself). Many -ся verbs in Russian are impersonal or have a special idiomatic meaning.

прийтись by itself often means something like to suit, to fit, to be just right:
- Тебе придётся по вкусу. – You will like it (it will suit your taste).

In the structure кому-то придётся + infinitive, it has developed a specific modal meaning: someone will have to do something. You don’t need to interpret -ся literally here; just learn придётся as part of the fixed pattern кому-то придётся + infinitive.

Why is the verb after придётся in the infinitive (остаться)?

After придётся, Russian uses the infinitive to show what action the person will have to do.

Pattern:

Кому?
- придётся
  - что сделать? (infinitive)

In this sentence:

Ей (to her)
придётся (will be necessary)
остаться (to stay)

This is similar to English “have to + infinitive”:

She will have to stay.
Ей придётся остаться.

Other examples:

Мне придётся работать. – I will have to work.
Им придётся уехать. – They will have to leave.

Why is it остаться, not оставаться?

Остаться and оставаться are the perfective and imperfective forms of the same verb pair:

оставаться – to be staying, to remain (process, ongoing, habitual)
остаться – to stay, to remain (completed result: “end up staying”)

In this sentence, остаться (perfective) is used because:

we are talking about one specific occasion in the future;
the focus is on the result: she will end up staying longer than usual, at least once.

Compare:

Ей приходится оставаться на работе дольше.
– She has to stay at work longer (regularly, as a habit).
Ей придётся остаться на работе дольше.
– She will have to stay at work longer (on this occasion).

So: придётся (future, one-time obligation) naturally pairs with остаться (perfective, one-time completed action).

What does остаться на работе literally mean? Why на работе and not в работе?

Literally:

остаться – to stay / to remain
на работе – (lit.) on work, but idiomatically “at work”

На работе is the standard expression for “at one’s workplace”:

Я сейчас на работе. – I’m at work now.
Он останется на работе до позднего вечера. – He will stay at work until late evening.

Using в работе would usually mean something different: “in the work / in the process of working / in the job”, not “at the workplace”. For example:

В работе над проектом были ошибки. – There were mistakes in the work on the project.

So for location (at work = in the workplace), Russian uses на работе, not в работе.

What is дольше grammatically? Is it from долгий or долго?

Дольше is the comparative form of the adverb долго (long [in time]).

долго – long, for a long time
дольше – longer (for a longer time)

So the structure:

дольше, чем обычно – longer than usual

It’s similar to:

быстро → быстрее (fast → faster)
много → больше (much / a lot → more)
долго → дольше (long → longer)

You would not normally say “более долго, чем обычно” in everyday speech; дольше is the natural comparative form.

Why is there a comma before чем обычно?

In Russian, comparisons with чем often introduce a comparative clause, and a comma is commonly used to separate it, especially when the comparison is a bit longer or forms a distinct phrase.

Here we have:

дольше, чем обычно – longer than usual

This is treated similarly to:

быстрее, чем вчера – faster than yesterday
лучше, чем раньше – better than before

The comma is standard here in careful writing. In very short, tight comparisons (especially with adjectives inside noun phrases) you may sometimes see no comma, but дольше, чем обычно with a comma is the normal, correct punctuation.

What exactly does чем обычно mean, and how is it used?

Чем обычно literally means “than (what is) usual”.

чем – than (used in comparisons)
обычно – usually, normally

So:

дольше, чем обычно – longer than (she) usually (does) / longer than usual

You can use чем обычно after many comparatives:

Он сегодня спокойнее, чем обычно. – He is calmer than usual today.
Тут холоднее, чем обычно. – It’s colder than usual here.
Она пришла раньше, чем обычно. – She came earlier than usual.

It’s a fixed comparative pattern: [comparative] + чем обычно.

Can the word order be changed? For example, can I say Ей остаться придётся на работе дольше, чем обычно?

Russian word order is flexible, but not every permutation sounds natural.

Your original sentence:

Ей придётся остаться на работе дольше, чем обычно.
is natural and neutral.

Some variations that are still acceptable (though with slight changes in emphasis):

Ей придётся дольше остаться на работе, чем обычно.
(unusual, slightly clunky; дольше is better near the comparison)
На работе ей придётся остаться дольше, чем обычно.
(emphasizes at work)

But:

Ей остаться придётся на работе дольше, чем обычно.
sounds awkward and unnatural. Splitting придётся and its infinitive остаться this way is not typical here.

Safest and most natural is exactly:

Ей придётся остаться на работе дольше, чем обычно.

Could I say Она должна будет остаться на работе дольше, чем обычно instead? What’s the difference from Ей придётся…?

Yes, you can say:

Она должна будет остаться на работе дольше, чем обычно.

This is grammatically fine, but there is a nuance difference:

Ей придётся остаться…
- Sounds more impersonal: circumstances force her.
- Often feels slightly softer / less direct: She’ll end up having to stay…
Она должна будет остаться…
- More directly modal: she must / will be obliged to.
- Slightly more formal or explicit about obligation, like a rule or order.

In many everyday contexts they are interchangeable, but ей придётся is more idiomatic for “she will have to (because that’s how things turned out)”.

How do you pronounce this sentence and where are the main stresses?

Here is the sentence with stressed syllables marked in CAPS:

ЕЙ приДЁтся осТÁться на раБОте ДÓльше, чем обЫЧно.

Approximate breakdown:

Ей – yei (like “yay” but with a softer “y”)
приДётся – pri-DYOT-sya (yo as in “yoga”)
остÁться – as-TÁ-tsa
на – na
раБОте – ra-BO-te (BO stressed)
ДÓльше – DÓL-she
чем – chem (like “chem” with a soft ch)
обЫчно – a-BYCH-na (BY is stressed; чн sounds like “ch-n”)

Spoken naturally, the sentence flows roughly like:

Ей придЁтся остАться на рабОте дОльше, чем обЫчно.