Ljeti nosim majicu od pamuka, dok zimi oblačim pulover od vune.

Ljeti and zimi are very common Croatian adverbial forms meaning in summer and in winter.

They work like time adverbs, so you can use them without a preposition:

• Ljeti = in summer
• Zimi = in winter

These are very natural in everyday Croatian. A learner should simply get used to them as fixed time expressions.

This is a very common question.

• nositi = to wear, to have on
• oblačiti = to put on, to dress oneself, and sometimes more broadly to wear

So:

• nosim majicu = I wear a T-shirt
• oblačim pulover = literally I put on a sweater

In this sentence, the present tense is being used for a habitual action, so oblačim pulover can be understood as I wear/put on a sweater in winter.

A native speaker might also say:

• Ljeti nosim majicu od pamuka, a zimi nosim pulover od vune.

That would also be perfectly natural.

Because majicu is in the accusative singular.

The verb nosim takes a direct object, so majica changes form:

• nominative: majica
• accusative: majicu

So:

• majica = a T-shirt / T-shirt as the subject form
• nosim majicu = I wear a T-shirt

This is a standard feminine noun pattern in Croatian.

Because pulover is a masculine inanimate noun, and in Croatian the accusative singular of masculine inanimate nouns is usually the same as the nominative singular.

So:

• nominative: pulover
• accusative: pulover

That is why you get:

• oblačim pulover

not pulovera.

You would see -a in the accusative for many masculine animate nouns, but pulover is inanimate.

Because after od meaning of / made of / from, Croatian normally uses the genitive.

So:

• od pamuka = of cotton / made of cotton
• od vune = of wool / made of wool

The base nouns are:

• pamuk = cotton
• vuna = wool

But after od, they become:

• pamuka
• vune

This is a very important pattern:

• stol od drveta = table made of wood
• čaša od stakla = glass made of glass
• haljina od svile = dress made of silk

Yes, absolutely.

Croatian often expresses material in two ways:

1. od + genitive

   • majica od pamuka
   • pulover od vune

2. an adjective

   • pamučna majica
   • vuneni pulover

Both are natural. Very roughly:

• od pamuka / od vune emphasizes the material a bit more directly
• pamučna / vuneni is often a bit more compact and adjective-like

In many situations, both are interchangeable.

Here dok means something like while, whereas, or while on the other hand.

In this sentence, it links two contrasting habits:

• Ljeti nosim majicu od pamuka
• dok zimi oblačim pulover od vune

So the idea is:

• In summer I wear a cotton T-shirt, whereas in winter I put on a wool sweater.

It is not only about simultaneous time here; it also creates a contrast between summer and winter.

Yes.

Even though the verbs are in the present tense:

• nosim
• oblačim

the sentence does not mean only what is happening right now. Because of ljeti and zimi, it describes a general habit or usual practice:

• In summer I wear...
• In winter I wear/put on...

This is very normal in Croatian, just as in English:

• I drink tea in the morning.
• Ljeti nosim majicu...

Both are habitual present.

Because Croatian has no articles.

So majicu can mean:

• a T-shirt
• the T-shirt

and pulover can mean:

• a sweater
• the sweater

The exact meaning depends on context.

That is different from English, where you must usually choose between a/an and the.

Croatian word order is fairly flexible, though some orders sound more natural than others.

This sentence is very natural as written:

• Ljeti nosim majicu od pamuka, dok zimi oblačim pulover od vune.

But you could also change it for emphasis, for example:

• Zimi oblačim pulover od vune, dok ljeti nosim majicu od pamuka.

Putting ljeti and zimi near the front is common because they set the time frame immediately.

So the word order is not completely fixed, but it is not random either.

Not necessarily.

On its own, oblačim can mean:

• I am putting on
• I put on
• I wear/dress in, depending on context

In this sentence, because of ljeti and zimi, the meaning is habitual, not a single action happening this moment.

So here it is better understood as something like:

• in winter I put on / wear a wool sweater

The time words make the meaning clear.

A few sounds may stand out to an English speaker:

• lj in ljeti is a special Croatian sound, something like a softened l
• j is pronounced like English y
• c is pronounced like ts
• č is pronounced like ch in church

So approximately:

• ljeti ≈ LYE-ti
• majicu ≈ ma-YI-tsu
• pulover ≈ pu-LO-ver

These are only rough guides, but they can help at first.

Yes, it is natural and correct.

It sounds like a normal descriptive sentence about seasonal clothing habits. A native speaker might make small stylistic changes, such as using a instead of dok, or using nosim in both clauses, but the original sentence is completely fine:

• Ljeti nosim majicu od pamuka, dok zimi oblačim pulover od vune.

It is a good example of:

• seasonal adverbs
• present tense for habits
• accusative direct objects
• od + genitive for material