Danas sam sama kod kuće, ali večeras nećeš biti sama.

In Serbian, subject pronouns are often left out because the verb form already shows who the subject is.

• sam = I am
• nećeš biti = you will not be

So:

• Danas sam sama kod kuće already means Today I am home alone
• večeras nećeš biti sama already means this evening you will not be alone

You can add ja or ti for emphasis, but it is not necessary.

Sama means alone or by oneself, and it agrees with the person it describes.

It appears twice because it describes two different subjects:

• sam sama = I am alone
• nećeš biti sama = you will not be alone

In both parts, the speaker is talking to or about a female person, so the feminine form sama is used.

Related forms:

• sam = masculine singular
• sama = feminine singular
• sami = masculine plural or mixed group
• same = feminine plural

So if a man said the first part, it would be:

• Danas sam sam kod kuće

Usually sama here means alone / by oneself, not necessarily lonely.

So:

• Danas sam sama kod kuće = Today I’m home alone

If you want to say lonely in an emotional sense, Serbian more often uses words like usamljena.

That means this sentence is most naturally about physical company, not feelings.

Because Serbian uses the verb biti = to be plus an adjective.

• sam = am
• sama = alone

So literally it is something like:

• Today am alone at home

This is completely normal in Serbian. The adjective does the describing, and the verb sam connects the subject to that description.

This is a very common Serbian word-order rule. Short forms like sam, si, je, smo, ste, su often behave like clitics and tend to come near the beginning of the sentence, usually in the second position.

So:

• Danas sam sama kod kuće

not usually:

• Danas sama sam kod kuće

The same type of rule affects many short forms in Serbian, so this is something learners notice again and again.

Kod kuće means at home.

It is a fixed expression and is extremely common. Even though kod often means something like at someone’s place / by / with, in kod kuće the whole phrase simply means at home.

So:

• kod kuće = at home

This is more natural than trying to translate English word for word.

They are not the same.

• kod kuće = at home
• u kući = in the house

Kod kuće refers to being at one’s home in a general sense.

U kući refers more literally to being inside a house/building.

So in this sentence, kod kuće is the natural choice because the meaning is about being home, not specifically about physical location inside a building.

Because many time expressions in Serbian can stand on their own as adverbs.

• danas = today
• večeras = this evening / tonight

You do not need a preposition before them here.

So Serbian says:

• Danas...
• Večeras...

just as English says:

• Today...
• Tonight...

This is the future tense in the negative.

• ćeš is part of the future construction
• nećeš = you will not
• biti = to be

So:

• nećeš biti sama = you will not be alone

This is the normal way to form the negative future of to be in Serbian.

Also note the standard spelling:

• nećeš is written as one word

not:

• ne ćeš

Because Serbian forms the future with a present form of hteti plus the infinitive of the main verb in many standard constructions.

Here the main verb is biti = to be.

So:

• nećeš biti = you will not be

This is completely normal and one of the basic future-tense patterns learners need to know.

Yes, Serbian word order is flexible, but not every version sounds equally natural.

The given sentence:

• Danas sam sama kod kuće, ali večeras nećeš biti sama.

is natural and neutral.

You might move things around for emphasis, for example:

• Večeras sama nećeš biti
• Sama večeras nećeš biti

These are possible in poetic, dramatic, or strongly emphatic contexts, but the original version is the most straightforward for everyday use.

Ali means but.

It connects two contrasting ideas:

• Today I am alone at home
• but this evening you will not be alone

So the speaker contrasts my situation now with your situation later.

This is a very common coordinating conjunction in Serbian.

Yes. Repeating sama creates a neat contrast and makes the sentence feel balanced:

• I am alone now
• you will not be alone tonight

It can sound comforting, suggestive, protective, or simply informative depending on context. Grammatically it is straightforward, but stylistically the repetition helps tie the two clauses together.

Only the adjective would change to match gender.

If both speaker and listener were male:

• Danas sam sam kod kuće, ali večeras nećeš biti sam.

If the speaker were female and the listener male:

• Danas sam sama kod kuće, ali večeras nećeš biti sam.

If the speaker were male and the listener female:

• Danas sam sam kod kuće, ali večeras nećeš biti sama.

The verb forms stay the same; the adjective changes to agree with the person described.