Čim moja sestra dođe kući, odmah će početi da kuva.

Čim means as soon as. It shows that one action happens immediately after another.

So in this sentence:

Čim moja sestra dođe kući, odmah će početi da kuva.

the idea is:

As soon as my sister gets home, she will immediately start cooking.

Compared with kad:

• kad = when
• čim = as soon as

Čim is more specific and usually suggests very little or no delay between the two actions.

Because after conjunctions like čim, Serbian often uses the present tense form of a perfective verb to refer to a future event.

Here:

• doći = to come / to arrive (perfective)
• dođe = present-tense form of that perfective verb

Even though dođe looks like a present tense, in this kind of sentence it refers to the future:

• Čim moja sestra dođe kući... = As soon as my sister gets home...

Using dolazi would sound wrong here if you mean a single completed arrival in the future, because:

• dolaziti = imperfective, repeated/ongoing coming
• doći = perfective, one completed arrival

Since arriving home is a single completed event, dođe is the natural choice.

This is a very common Serbian pattern.

In subordinate clauses introduced by words like:

• kad = when
• čim = as soon as
• ako = if

Serbian often does not use future tense with će the way English does. Instead, it often uses:

• a present form, especially of a perfective verb, to refer to the future

So:

• Čim moja sestra dođe kući...
  not usually
• Čim će moja sestra doći kući...

This is similar to English in a way: English also says:

• When she gets home, ... not
• When she will get home, ...

So the Serbian pattern is very natural here.

Kući is a very common idiomatic form meaning home, especially after verbs of motion like doći.

So:

• doći kući = to come home
• ići kući = to go home

This is the normal way to say it.

A few comparisons:

• kući = home, in the sense of destination after motion
• kod kuće = at home
• u kuću = into the house

So:

• Došla je kući. = She came home.
• Ona je kod kuće. = She is at home.
• Ušla je u kuću. = She entered the house.

In your sentence, the meaning is simply gets home, so kući is exactly right.

Good question. Both words suggest quick timing, but they do slightly different jobs.

• čim links the two actions: as soon as
• odmah emphasizes that the second action happens immediately

So together they strengthen the idea:

• Čim moja sestra dođe kući, odmah će početi da kuva.

This is a bit like English:

• As soon as my sister gets home, she’ll start cooking immediately.

In English, that may sound slightly repetitive, but in Serbian this kind of reinforcement is very natural.

You could omit odmah:

• Čim moja sestra dođe kući, počeće da kuva.

That still works, but odmah adds emphasis.

Both are possible.

• počeće = one-word future form
• će početi = split future form

In modern Serbian, both are used, and the choice is often about style, rhythm, or word order.

So these are both correct:

• Odmah će početi da kuva.
• Odmah počeće da kuva. — this one is less natural because of clitic placement
• Počeće odmah da kuva.
• Odmah će početi da kuva. — very natural

The form će početi is especially common when something comes before the future auxiliary, because će is a clitic and tends to take the second position in the clause.

In odmah će početi da kuva, odmah comes first, so će naturally comes right after it.

Će is the auxiliary used to form the future tense in Serbian.

Here:

• će početi = will start

So the second clause is:

• odmah će početi da kuva = she will immediately start cooking

The full future tense is made with:

• a form of hteti as an auxiliary (ću, ćeš, će, ćemo, ćete, će)
• plus the infinitive or related future construction

Here the subject is third person singular (moja sestra), so the auxiliary is će.

In Serbian, after verbs like početi (to start/begin), it is very common to use:

• da + present tense

So:

• početi da kuva = to start cooking

This is the most natural pattern in everyday Serbian.

You may also see an infinitive after početi:

• početi kuvati

But that sounds more formal, literary, regional, or more typical of Croatian usage than of everyday Serbian.

For a learner of Serbian, početi da kuva is the safest and most natural choice.

Because after da, Serbian usually uses a finite verb form, not the infinitive.

So:

• da kuva = literally something like that she cooks / to cook in this structure

Here kuva is the 3rd person singular present, matching moja sestra.

Compare:

• Počinjem da kuvam. = I am starting to cook.
• Počinješ da kuvaš. = You are starting to cook.
• Počinje da kuva. = He/She is starting to cook.

So kuva is there because the subject is moja sestra.

Because početi usually combines naturally with an imperfective verb when you mean starting an activity.

• kuvati / kuva = to cook / is cooking (imperfective, ongoing process)

That makes sense, because you normally start doing an action, not start completing it.

So:

• početi da kuva = start cooking

If you used a perfective verb such as skuvati (to cook completely / to finish cooking), the meaning would shift and usually sound less natural in this context.

The sentence focuses on the beginning of the activity, so the imperfective kuva is the expected form.

Yes. Serbian word order is flexible, though not completely free.

The original sentence:

• Čim moja sestra dođe kući, odmah će početi da kuva.

is very natural.

You could also say:

• Odmah će početi da kuva čim moja sestra dođe kući.

That still means the same thing, but it puts the main clause first.

You can also move odmah for emphasis:

• Čim moja sestra dođe kući, počeće odmah da kuva.
• Čim moja sestra dođe kući, počeće da kuva odmah.

These are possible, but the original version sounds especially smooth and natural.

So yes, word order can change, but the placement of clitics like će still follows Serbian rules.

The noun phrase moja sestra is necessary here if you want to say specifically my sister.

Serbian often drops subject pronouns like ja, ti, on, ona, because the verb form already shows the person. But here the subject is not just a pronoun — it is a full noun phrase:

• moja sestra = my sister

If you remove it, the sentence becomes:

• Čim dođe kući, odmah će početi da kuva.

That means:

• As soon as she gets home, she will immediately start cooking.

This is fine only if it is already clear from context who she is. So yes, Serbian can leave the subject out, but only when the listener already knows it.

This sentence is a nice example of Serbian aspect.

1. doći → dođe

• perfective
• refers to a single completed arrival

Why perfective? Because getting home is seen as one completed event.

2. početi → će početi

• perfective
• refers to the beginning of an action as a single event

Why perfective? Because starting is treated as a completed point-like event.

3. kuvati → kuva

• imperfective
• refers to the ongoing activity of cooking

Why imperfective? Because cooking is viewed as a process.

So the structure is very logical:

• first, one completed event: she gets home
• then, one completed event: she starts
• then, an ongoing activity: cooking

Yes, in many contexts that would be a good English translation.

Depending on tone, čim can be rendered as:

• as soon as
• once

So:

• Čim moja sestra dođe kući, odmah će početi da kuva.

could be translated as:

• As soon as my sister gets home, she’ll immediately start cooking.
• Once my sister gets home, she’ll immediately start cooking.

Usually as soon as is the closest and most direct match for čim.