Kad govori polako, svatko ga razumije.

Yes. Kad means when here.

In this sentence, Kad govori polako means When he speaks slowly.

A learner may also see kada, which is a slightly fuller form of the same word. In everyday speech, kad is very common and natural.

So:

• Kad govori polako... = When he speaks slowly...
• Kada govori polako... = same meaning, just a different form

Croatian often leaves out subject pronouns when they are not needed. The verb ending already shows the person and number.

Govori is 3rd person singular present, so it means:

• he speaks
• she speaks
• it speaks

Because of that, Croatian usually does not need to say on (he) or ona (she) unless you want emphasis or contrast.

So:

• Kad govori polako... = When he/she speaks slowly...
• Kad on govori polako... = When he speaks slowly... with extra emphasis on he

Govori is the present tense form of the verb govoriti (to speak, to talk).

Here it is:

• govoriti = to speak
• govori = he/she speaks

This is 3rd person singular present tense.

Because Croatian uses the same form for he, she, and it, the exact subject often has to be understood from context.

Polako is an adverb, and here it means slowly.

So:

• govori polako = speaks slowly

A useful point: polako can also be used in other situations with meanings like slowly, carefully, take it easy, depending on context.

But in this sentence, it simply describes how he speaks: slowly.

Svatko means everyone or everybody.

Even though it refers to many people, grammatically it behaves like a singular word. That is why the verb is singular:

• svatko razumije = everyone understands

This is similar to English in a way:

• Everyone understands him.

English also uses a singular verb with everyone.

Because ga is the object pronoun, while on is the subject pronoun.

In this sentence, the person is being understood by others, so he is the object of razumije (understands).

So:

• on = he (subject)
• ga = him (object)

That is why Croatian says:

• svatko ga razumije = everyone understands him

not svatko on razumije

Here ga is in the accusative case, because it is the direct object of razumije.

The verb razumjeti (to understand) takes a direct object:

• understand him
• understand her
• understand them

So in Croatian:

• ga = him in the accusative

More precisely, ga is a short unstressed pronoun, often called a clitic.

Because ga is a clitic, and Croatian clitics usually appear near the beginning of the clause, often in the second position.

So in:

• svatko ga razumije

the word order is natural because:

• svatko = first element
• ga = clitic in second position
• razumije = main verb

This is one of the big differences from English. English says:

• everyone understands him

but Croatian often places short pronouns earlier:

• svatko ga razumije

Yes, that is also correct, but it is not exactly the same in structure.

Compare:

• svatko ga razumije = everyone understands him
• svi ga razumiju = all of them understand him / everyone understands him

The meaning is very similar, but:

• svatko is grammatically singular, so razumije
• svi is plural, so razumiju

So both are possible, but the grammar changes with the subject word.

Razumije is the 3rd person singular present tense of razumjeti (to understand).

So:

• razumjeti = to understand
• razumije = he/she understands

In this sentence, the subject is svatko (everyone), which is singular, so the verb is singular too:

• svatko ga razumije

The comma separates the introductory clause from the main clause.

The sentence has two parts:

• Kad govori polako = subordinate clause
• svatko ga razumije = main clause

So the comma works much like in English:

• When he speaks slowly, everyone understands him.

This kind of comma is very normal in Croatian.

Yes, Croatian word order is more flexible than English, but not every change sounds equally natural.

For example, these are possible:

• Kad govori polako, svatko ga razumije.
• Kad polako govori, svatko ga razumije.

Both are natural.

But you must still be careful with clitics like ga, because they have special placement rules. So you cannot move words around completely freely.

The original sentence is very natural and standard.

It can often suggest either, depending on context.

Croatian present tense with kad can express:

• a general truth or repeated situation: Whenever he speaks slowly, everyone understands him
• a simple present-time relation: When he speaks slowly, everyone understands him

In a sentence like this, many learners will naturally understand it as a general statement: Whenever he speaks slowly, everyone understands him.

Yes. By itself, govori does not tell you whether the subject is male or female.

It can mean:

• he speaks
• she speaks

The reason many translations use he here is the later pronoun ga, which means him. That tells you the person being understood is male.

So in the full sentence, the most natural reading is:

• When he speaks slowly, everyone understands him.

Svatko is normal standard Croatian and is used in everyday language.

It is not unusually formal. It is a very common word for everyone/everybody.

You may also hear related forms in different contexts, but svatko itself is completely normal and useful to learn early.