Veterinar pregleda psa.

Because psa is the accusative singular form of pas.

In this sentence, pas is the direct object: it is the one being examined. Serbian changes noun forms according to their role in the sentence.

• pas = nominative singular, the basic dictionary form
• psa = accusative singular, used here for the object

A very useful rule:

• for masculine animate nouns, the accusative singular usually looks like the genitive singular
• so pas → psa

That is why you say Veterinar pregleda psa, not Veterinar pregleda pas.

Veterinar is in the nominative singular.

It is the subject of the sentence, meaning it is the one doing the action. In Serbian, subjects are normally in the nominative.

So here:

• veterinar = the veterinarian, subject
• psa = the dog, object

Mostly from the case endings, not just from word order.

In Veterinar pregleda psa:

• veterinar is nominative, so it is the subject
• psa is accusative, so it is the object

That means the veterinarian examines the dog, not the other way around.

This is one reason Serbian can have more flexible word order than English. Even if you changed the order to Psa pregleda veterinar, the endings still show that the veterinarian is doing the examining.

Pregleda is the 3rd person singular verb form.

It matches a subject like:

• on = he
• ona = she
• ono = it
• or a singular noun such as veterinar

So veterinar pregleda means the veterinarian examines.

The verb ending tells you that the subject is singular and third person.

Grammatically, yes, it is a present-tense form, but there is an important aspect point.

The verb pregledati is typically perfective, and perfective present forms in Serbian often do not behave exactly like the ordinary English simple present. In many contexts, they can sound more like a future or completed action.

If you want a clearly ongoing or habitual present, Serbian often prefers the imperfective verb pregledavati:

• Veterinar pregledava psa. = The veterinarian is examining / examines the dog.

So in a beginner sentence, Veterinar pregleda psa may be given as a simple model, but in real usage, pregledava is often more natural for a plain present meaning.

Because Serbian has no articles.

English says:

• a veterinarian
• the veterinarian
• a dog
• the dog

Serbian usually just says:

• veterinar
• pas / psa

The exact meaning depends on context. So Veterinar pregleda psa could mean:

• The veterinarian examines the dog
• A veterinarian examines a dog
• The veterinarian examines a dog
• A veterinarian examines the dog

In practice, context tells you which one is meant.

Yes. Serbian word order is much more flexible than English word order.

The neutral order here is:

• Veterinar pregleda psa.

But you can also say:

• Psa pregleda veterinar.

That version puts more focus on psa.

Because the case endings show the roles, Serbian does not rely as heavily on word order as English does. Still, not every order sounds equally neutral. Veterinar pregleda psa is the most straightforward and natural basic version.

No. Serbian usually does not need a subject pronoun when the subject is already clear.

So you normally say:

• Veterinar pregleda psa.

not:

• On veterinar pregleda psa.

The pronoun on would only be added for emphasis or contrast, and even then not in that position with the noun like in English. Serbian generally avoids unnecessary subject pronouns.

Veterinar is the masculine form.

For a female veterinarian, Serbian often uses:

• veterinarka

So:

• Veterinar pregleda psa. = A male veterinarian / a veterinarian examines the dog.
• Veterinarka pregleda psa. = A female veterinarian examines the dog.

In some contexts, the masculine form can be used more generally, but veterinarka is the normal specific feminine form.

It is:

• Ветеринар прегледа пса.

Serbian commonly uses both scripts:

• Latin: Veterinar pregleda psa.
• Cyrillic: Ветеринар прегледа пса.

They are equivalent.