График у неё сменный, поэтому в пятницу она работает вечером, а в субботу отдыхает.

У неё is a very common Russian way to express possession, especially in everyday speech.

• У неё сменный график = She has a shift schedule
• Literally, у неё means by her / at her, but in Russian this structure often means someone has something

So:

• У неё сменный график = neutral, very natural
• Её график сменный = Her schedule is shift-based, also correct, but it sounds a bit more directly focused on her schedule as the topic

In your sentence, График у неё сменный is a stylistic word order that highlights график first.

Because сменный is an adjective agreeing with график.

• график is masculine
• so the adjective must also be masculine singular
• therefore: сменный график

Compare:

• сменная работа — feminine
• сменное расписание — neuter
• сменный график — masculine

Russian adjectives must match the noun in gender, number, and case.

Сменный график means a shift schedule or rotating work schedule.

It comes from смена, which means shift. So if someone has a сменный график, their work hours are not the same every day. They may work mornings one day, evenings another day, and have different days off.

So this phrase is commonly used for jobs with non-standard hours:

• hospitals
• stores
• factories
• service jobs
• transport, etc.

Both are correct, but the word order changes the emphasis.

• У неё сменный график = more neutral, standard
• График у неё сменный = puts extra focus on график

Russian word order is more flexible than English word order. Speakers often move words around to highlight what is already known, what is important, or what contrasts with something else.

So here, starting with График can feel a bit like:

• As for her schedule, it’s shift-based
• or Her schedule is shift-based

After в when talking about on a day of the week, Russian uses the accusative case.

So:

• пятница → в пятницу
• суббота → в субботу

This is the normal pattern for many feminine days ending in -а.

Examples:

• в среду — on Wednesday
• в пятницу — on Friday
• в субботу — on Saturday

So the sentence uses accusative because it means on Friday and on Saturday.

Вечером is the normal adverbial form meaning in the evening.

It is the instrumental case of вечер, but in expressions of time it functions almost like an adverb.

Common time expressions like this are:

• утром — in the morning
• днём — during the day / in the daytime
• вечером — in the evening
• ночью — at night

So Russian usually says:

• Она работает вечером not
• Она работает в вечер

The form в вечер is generally not used for this meaning.

Because the sentence describes a usual schedule or regular arrangement, not something happening only right now.

In Russian, the present tense of the imperfective verb is used for:

• habits
• routines
• repeated actions
• schedules

So:

• она работает вечером = she works in the evening / she is scheduled to work in the evening
• в субботу отдыхает = she rests / she has Saturday off

This is similar to English using the present for schedules:

• She works Friday evening
• The train leaves at six

А often marks a contrast or comparison between two pieces of information.

Here the sentence contrasts:

• Friday — she works
• Saturday — she rests

So а is very natural because it sets one situation against another.

Compare:

• и = simple addition: and
• но = stronger contradiction: but
• а = contrast/juxtaposition: whereas / while / and

In this sentence, а is the best choice because the idea is not a dramatic contradiction, just a contrast between two days.

Поэтому means therefore, so, or that’s why.

It connects the first idea with the result:

• График у неё сменный — her schedule is shift-based
• поэтому... — therefore / so...

So the logic is: Because her schedule is shift-based, on Friday she works in the evening, and on Saturday she rests.

It is a very common connector in Russian for showing cause and result.

Yes, very often it could be omitted.

Russian often leaves out subject pronouns when the subject is clear from the verb form or context. So this would also be natural:

График у неё сменный, поэтому в пятницу работает вечером, а в субботу отдыхает.

However, keeping она can make the sentence:

• clearer
• slightly more balanced
• a little more explicit

So both are possible. Including она is not wrong at all.

Yes. Отдыхает literally means rests, relaxes, or takes time off.

In work-schedule contexts, it often means:

• she is off
• she has the day off
• she is not working

So in this sentence, в субботу отдыхает naturally means that Saturday is her rest day or day off.

Russian often uses отдыхать in this broader sense, not only for physical resting but also for being free from work.