Система уже работает.

Russian does not have articles, so there is no separate word for the or a/an.

So система can mean:

• the system
• a system

Which one you choose in English depends on context. In an isolated sentence like this, the system is often the most natural translation.

Система is in the nominative singular form because it is the subject of the sentence, the thing doing the action.

Basic breakdown:

• система = subject, system
• уже = already
• работает = works / is working / is operating

Because система is the subject, it stays in the dictionary form here.

Уже means already.

It often suggests that something has happened or become true by this point, sometimes a little earlier than expected, or after waiting for it.

So Система уже работает can feel like:

• The system is already working.
• The system is up and running now.
• The system works now already, in the sense of it’s functioning now.

In conversation, уже often adds a sense of progress or change of state.

Работает is the 3rd person singular present-tense form of работать.

So:

• я работаю = I work / am working
• ты работаешь = you work / are working
• он/она работает = he/she works / is working
• система работает = the system works / is working

It agrees with система, which is singular.

In Russian, the present tense usually does not distinguish between:

• simple present: works
• present continuous: is working

So работает can cover both meanings.

Which English translation is best depends on context:

• If you mean general functioning: The system works.
• If you mean it is functioning right now: The system is working.
• With уже, English often prefers is already working or is already operational.

Работает focuses on the current state: the system is functioning.

If you specifically want to say that it started working, Russian often uses a different verb, usually заработать in the past:

• Система уже заработала. = The system has started working already / The system is up and running now.

So the difference is roughly:

• Система уже работает. = The system is already functioning.
• Система уже заработала. = The system has already started functioning.

This is partly an aspect difference:

• работать = imperfective, ongoing process/state
• заработать = perfective, entering that state

Yes. Russian word order is flexible, though the neutral order here is very natural:

• Система уже работает.

You may also hear:

• Уже работает система.
• Система работает уже.

These are all possible, but the emphasis changes.

Very roughly:

• Система уже работает. = neutral, normal statement
• Уже работает система. = emphasis on already
• Система работает уже. = possible, but often sounds more marked or context-dependent

For learners, the original order is the safest default.

A helpful stress-marked version is:

Систе́ма уже́ рабо́тает.

Approximate pronunciation:

• систе́ма = sis-TYE-ma
• уже́ = oo-ZHE
• рабо́тает = ra-BO-ta-yet

A few useful notes:

• The stress in систе́ма is on те́
• The stress in уже́ is on the last syllable
• The stress in рабо́тает is on бо́

As usual in Russian, unstressed vowels are reduced a bit in real speech.

It can describe both.

Работать is used for:

• people: Она работает в банке. = She works in a bank.
• machines/devices: Компьютер работает. = The computer is working.
• systems/programs/services: Система работает. = The system is working.

So with система, работает means functions / operates, not has a job.

There are two very common possibilities, and they mean different things:

• Система ещё не работает. = The system isn’t working yet.
• Система уже не работает. = The system no longer works / isn’t working anymore.

This is a very useful contrast:

• уже = already
• ещё не = not yet
• уже не = no longer

So word placement with не and уже matters a lot.

Not as a separate word.

In English, is working has two parts:

• is
• working

In Russian, работает alone expresses that whole idea: works / is working.

So you do not add a separate present-tense word for is here.

That is why:

• Система уже работает. is complete by itself.