Prodavac stavlja luk u kesu.

Because u can take different cases depending on meaning:

• u + accusative = movement into something
• u + locative = location in something

Here, the onion is being put into the bag, so kesa changes to the accusative singular: kesa → kesu.

Compare:

• stavlja luk u kesu = he is putting the onion into the bag
• luk je u kesi = the onion is in the bag

So kesu is required because there is motion toward the inside of the bag.

It is changing case, but for this kind of noun, the form happens to stay the same.

Luk is a masculine inanimate noun. In Serbian, masculine inanimate nouns usually have:

• nominative singular = luk
• accusative singular = luk

So the direct object is in the accusative, but the form does not visibly change.

This is different from masculine animate nouns. For example:

• prodavac = nominative
• vidim prodavca = accusative

So luk is accusative here, but it just looks identical to the nominative.

Stavlja is the 3rd person singular present tense of stavljati.

So it means:

• he/she puts
• he/she is putting

depending on context.

A very important point for learners is that stavljati is imperfective. That means it can describe:

• an ongoing action
• a habitual action
• a general process

Its perfective partner is usually staviti.

Compare:

• Prodavac stavlja luk u kesu. = The seller is putting / puts the onion into the bag.
• Prodavac je stavio luk u kesu. = The seller put the onion into the bag.

In this sentence, it is best understood as into.

Serbian often uses the same preposition, u, for both in and into, but the case tells you which meaning is intended:

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

Since the sentence has u kesu and kesu is accusative, the meaning is into the bag.

This is a very common Serbian pattern, and English speakers often need time to get used to it because English uses two different words, while Serbian often uses one preposition plus case.

Prodavac is in the nominative singular because it is the subject of the sentence.

It is the person doing the action.

So the basic structure is:

• Prodavac = subject, nominative
• stavlja = verb
• luk = direct object, accusative
• u kesu = prepositional phrase showing direction, u + accusative

This is a very standard Serbian sentence pattern.

Yes. Luk can mean:

• onion
• bow (the weapon)

Serbian often relies on context to tell you which meaning is intended.

In Prodavac stavlja luk u kesu, the natural interpretation is onion, because a seller putting an onion into a bag is a normal shopping situation.

If the context were about weapons, hunting, or archery, luk could mean bow instead.

Because Serbian does not have articles like English.

So Serbian does not normally use separate words corresponding to:

• a
• an
• the

Whether something is definite or indefinite is usually understood from:

• context
• word order
• emphasis
• the situation

So Prodavac stavlja luk u kesu could correspond to English in different ways depending on context, such as:

• The seller is putting an onion into a bag
• A seller is putting the onion into the bag

English requires articles; Serbian usually does not.

Not completely. Serbian word order is more flexible than English because cases show the grammatical roles.

The neutral, straightforward order here is:

• Prodavac stavlja luk u kesu.

But other orders are possible if you want to change emphasis, for example:

• Luk prodavac stavlja u kesu.
• U kesu prodavac stavlja luk.

These alternatives can sound marked or emphasize a particular part of the sentence.

So for learners, the safest choice is the basic order:

subject + verb + object + other information

That is exactly what this sentence uses.

Grammatically, prodavac is a masculine noun and usually refers to a male seller or salesperson.

The specifically feminine form is:

• prodavačica = female seller / saleswoman

So if you know the seller is female, you would normally say:

• Prodavačica stavlja luk u kesu.

In some contexts, masculine forms can be used more generally, but for everyday learning it is best to understand prodavac as masculine.

Lj is a single Serbian sound, not just a separate l plus j.

A rough English approximation is the sound in million for many speakers, though it is not always exactly the same.

So stavlja sounds roughly like:

• STAV-lya

Other useful pronunciation points in this sentence:

• c in prodavac is like ts
• u is like oo in food
• Serbian spelling is quite phonetic, so words are usually pronounced close to how they are written

So very roughly:

• Prodavac ≈ pro-DA-vats
• stavlja ≈ STAV-lya
• luk ≈ look
• u ≈ oo
• kesu ≈ KE-soo