Kada uđeš u zgradu, skreni levo; moj stan je tamo.

Kada means when.

Yes, in everyday Serbian, kad is very common and means the same thing. So these are both natural:

• Kada uđeš u zgradu, skreni levo.
• Kad uđeš u zgradu, skreni levo.

Kada can sound a bit more neutral or slightly more formal, while kad is very common in speech.

Uđeš is the 2nd person singular present tense form of the verb ući (to enter, to go in).

But there is an important point: ući is a perfective verb. In Serbian, the present tense of a perfective verb often refers to a future completed action, especially after words like kada (when).

So:

• kada uđeš u zgradu = when you enter the building / once you go into the building

It does not mean when you are entering in an ongoing sense. It means the action is viewed as completed: first you enter, then you turn left.

Because Serbian uses different cases depending on whether there is movement or location.

With u:

• u + accusative = movement into
• u + locative = being in

So:

• u zgradu = into the building
• u zgradi = in the building

In this sentence, you are moving into the building, so zgrada becomes zgradu in the accusative singular.

Skreni is the imperative form, meaning turn.

The sentence is giving an instruction:

• skreni levo = turn left

By contrast, skreneš is a present-tense form, not an imperative. You would use skreneš in structures like:

• Kad skreneš levo, videćeš vrata.
  When you turn left, you’ll see the door.

So:

• skreni = command
• skreneš = regular verb form used in clauses like when you turn...

Here levo is an adverb, meaning to the left / left.

In directions, Serbian often uses adverbs like:

• levo = left
• desno = right
• pravo = straight

So:

• skreni levo = turn left
• skreni desno = turn right
• idi pravo = go straight

You do not need an extra word like to. Serbian simply says turn left with levo.

Usually, this sentence strongly prefers uđeš.

Why? Because ući is perfective, and it expresses a single completed action: enter. The meaning is:

1. you enter the building
2. then you turn left

If you said ulaziš (from ulaziti, imperfective), it would sound more like an ongoing or repeated action, which is not the natural choice here.

So:

• kada uđeš u zgradu = natural: when you enter the building
• kada ulaziš u zgradu = more like when you are entering the building / when you enter buildings, depending on context

Because after time words like kada (when), Serbian normally does not use ću/ćeš/će the way English uses will.

English says:

• When you enter the building, turn left.

Not:

• When you will enter the building...

Serbian works similarly. After kada, you usually use a normal verb form, often a present form:

• Kada uđeš u zgradu...

So kada ćeš ući usually does not fit this kind of sentence.

Moj stan is in the nominative, because it is the subject of the clause:

• moj stan je tamo = my apartment is there

Breakdown:

• moj = my
• stan = apartment / flat
• je = is
• tamo = there

So the basic structure is just:

• [subject] + [is] + [there]

Yes, you could say stan je tamo, but it would usually sound less natural unless the context already makes it clear whose apartment you mean.

Serbian often omits possessives like my, your, etc. when the meaning is obvious. But in this sentence, moj stan is perfectly natural because it helps identify the apartment clearly.

So:

• moj stan je tamo = my apartment is there
• stan je tamo = the apartment is there

The second version may sound less specific unless the listener already knows which apartment you are talking about.

Tamo means there, usually at a place away from both speaker and listener, or simply at a place being pointed out in the conversation.

Common location words:

• ovde = here
• tu = there / here near you / right there
• tamo = there over there

So:

• Moj stan je tamo. = My apartment is there / over there.

In real speech, the exact difference between tu and tamo can depend on context, but tamo often suggests a place a bit more removed.

The letter đ is pronounced roughly like the sound in British English du in during for some speakers, or like a softer version of j in juice. There is no perfect English equivalent, but it is a soft d/j-type sound.

uđeš is approximately:

• OO-dyesh

Very roughly:

• u = oo
• đ = soft dj
• eš = esh

Also note that š sounds like sh.

So:

• uđeš sounds roughly like OO-dyesh

Yes, you can say that too.

Both are natural:

• Kada uđeš u zgradu, skreni levo.
• Skreni levo kada uđeš u zgradu.

The first version puts the time condition first: When you enter the building... The second version puts the command first: Turn left when you enter the building.

The meaning is basically the same. The difference is mostly in emphasis and flow.