Learn Hardcore Croatian: Baka mi je poslala dugo pismo iz kojeg se osjeća njena ljubav. - Grandmother sent me a long letter from which one can feel her love.

Clitic pronouns like mi, ti, mu, joj usually stand very early in the sentence, after the first stressed element. The auxiliary je is also a clitic, and Croatian has a fixed order for these clitics.

In a simple sentence like this, the natural order is:

Baka mi je poslala...
subject – dative pronoun – auxiliary – main verb

You could also say:

Baka je meni poslala dugo pismo. (using stressed meni instead of mi, for emphasis: to me specifically)

Why is it just baka, not moja baka, if the meaning is my grandma?

In Croatian, close family members are very often used without a possessive pronoun when the possessor is obvious from context.

Because the indirect object mi = to me is present, baka is naturally understood as my grandmother:

Baka mi je poslala... ≈ My grandma sent me...

Using moja baka is also correct:

Moja baka mi je poslala dugo pismo.

The version with moja just makes the possession explicit and may sound a bit more formal or explanatory. In everyday speech, especially when only one grandma is clearly in question, plain baka is very natural.

Why do we need je in Baka mi je poslala...? Can I say Baka mi poslala...?

Je is the auxiliary verb (present of biti = to be) used to form the past tense (the perfekt) in Croatian.

The structure of the past tense is:

present of biti (here: je) + past participle (poslala)

So:

Baka mi je poslala dugo pismo.
= Grandma has sent / sent me a long letter.

You cannot omit je in standard Croatian; Baka mi poslala... would be ungrammatical in standard language.

The only time the auxiliary can disappear is in some colloquial speech patterns (and usually only in specific persons or contexts), but learners should keep it:

Ja sam poslala... (I sent; if speaker is female)
Ti si poslao / poslala... (you sent)
On je poslao / Ona je poslala... (he / she sent)

Why is poslala ending in -la, and what would it look like with a different subject?

Poslala is the past participle of poslati (to send), and its ending agrees with the gender and number of the subject.

Here the subject baka is feminine singular, so:

poslala (feminine singular)

Other forms:

Djed mi je poslao pismo. (grandfather – masculine sg → poslao)
Mama mi je poslala pismo. (mother – feminine sg → poslala)
Roditelji su mi poslali pismo. (parents – plural → poslali)

So the pattern is:

masculine singular: poslao
feminine singular: poslala
neuter singular: poslalo (rare with people)
plural (any mixed or masculine group): poslali
feminine-only group: poslale

In dugo pismo, why is it dugo and not duga or something else?

Pismo (letter) is a neuter noun in Croatian. Adjectives must agree with the noun in gender, number, and case.

The base adjective is dug (long). In nominative/accusative neuter singular, it takes the form dugo:

masculine: dug
feminine: duga
neuter: dugo

So:

dug čovjek (a tall/long man – masculine)
duga reka (a long river – feminine)
dugo pismo (a long letter – neuter)

You might also hear dugačko pismo or dosta dugo pismo; these are stylistic variations. But duga pismo is wrong because pismo is not feminine.

Could dugo here mean for a long time, like Grandma wrote to me for a long time?

In this sentence dugo clearly functions as an adjective form agreeing with pismo, not as an adverb of time.

dugo pismo = a long letter (many words / many pages)

If you wanted to say She wrote to me for a long time, you would express it differently, for example:

Baka mi je dugo pisala. (literally: Grandma wrote to me for a long time.)

Note the difference:

dugo pismo – dugo describes pismo (adjective, neuter form).
dugo pisala – dugo describes pisala (adverb, duration of the action).

What is the function of iz in iz kojeg se osjeća njena ljubav, and why do we use kojeg?

Iz is the preposition from / out of. It always governs the genitive case.

The relative pronoun koji (which/that) must:

agree in gender and number with the noun it refers to (pismo – neuter singular), and
be in the case required by its role in the clause and by the preposition.

Here:

noun: pismo – neuter singular
preposition: iz → requires genitive
neuter singular genitive of koji is kojeg

So we get:

iz kojeg (pisma) = from which (letter)

Even though pismo is neuter, the genitive form is kojeg, which looks the same as masculine-genitive. This is just a property of the relative pronoun paradigm.

Could we also say pismo u kojem se osjeća njena ljubav instead of iz kojeg? Is there a difference?

Yes, u kojem is also possible and idiomatic:

pismo u kojem se osjeća njena ljubav
literally: a letter in which her love is felt

Subtle nuance:

iz kojeg (from which) suggests that the feeling of love somehow comes out of the letter, as if it radiates from it.
u kojem (in which) presents the love as something contained in the letter.

In practice, both can describe the same situation, and native speakers might choose either without thinking too much about the nuance. Both are good to learn and use.

What does se do in iz kojeg se osjeća njena ljubav? Is it reflexive like myself / yourself?

Here se is not reflexive in the sense of myself / yourself, but part of an impersonal / reflexive construction that often corresponds to English can be felt / one feels.

osjećati = to feel, to sense
osjećati se (impersonal with se) = to be felt / to be sensed

So:

iz kojeg se osjeća njena ljubav ≈ from which her love can be felt or from which you can feel her love

No specific subject is doing the feeling; it’s more like a general, impersonal feeling that arises. Croatian often uses se to create these impersonal or passive-like meanings:

Ovdje se puši. – Smoking is done here / People smoke here.
Ovdje se osjeća dim. – You can smell smoke here.

Why is it osjeća and not osjeti? What is the aspect difference here?

Osjećati and osjetiti form an aspect pair:

osjećati – imperfective (ongoing, repeated, continuous feeling)
osjetiti – perfective (a single, completed act of feeling or noticing)

In this sentence:

iz kojeg se osjeća njena ljubav
describes a general, continuous quality of the letter: whenever you read it, you can feel that love, it’s always present in it.

If you said:

iz kojeg se osjeti njena ljubav

this would sound more like a single moment of realization: at some point, the love is suddenly felt or noticed. It is possible in some contexts but less natural for describing a lasting, inherent quality of the letter. That’s why the imperfective osjeća is used.

What is the difference between njena and njezina? Which one is correct in njena ljubav?

Both njena and njezina mean her and are correct possessive adjectives of ona (she).

njena ljubav
njezina ljubav

Both are grammatically fine. There are some regional and stylistic preferences:

In much of Croatia, the shorter forms njegov / njen / njihov are very common in everyday speech.
The longer forms njezin / njezina are often considered somewhat more standard or formal, and some style guides prefer them, especially in writing.

For a learner, it is enough to know:

You may encounter both njena ljubav and njezina ljubav; they mean the same thing.
Nominative feminine singular is njena / njezina.
In other cases, the endings change:
- bez njezine ljubavi (genitive)
- s njezinom ljubavlju (instrumental), etc.

In this sentence, nominative is needed because njena ljubav is the subject of osjeća se.

Why is it njena ljubav in the nominative, not a genitive like njezine ljubavi?

In the clause iz kojeg se osjeća njena ljubav, the grammatical subject of the verb osjeća se is njena ljubav.

So:

što se osjeća? – njena ljubav
What is felt? Her love.

Because it is the subject, njena ljubav is in the nominative case.

If you changed the structure so that love is no longer the subject, you might use a different case. For example:

Osjećam njezinu ljubav. – I feel her love.
Here njezinu ljubav is direct object (accusative), not subject.

In the original sentence, the pattern is:

[iz kojeg] se [osjeća] [njena ljubav]
prepositional phrase – clitic se – verb – subject

Can I change the word order in the last part? For example, say iz kojeg se njezina ljubav osjeća?

Yes, Croatian word order is relatively flexible, especially in the second clause, as long as the clitic se stays in an allowed clitic position.

Possible versions include:

iz kojeg se osjeća njena ljubav (very natural, neutral)
iz kojeg se njezina ljubav osjeća (slightly more emphasis on njezina ljubav)
iz kojeg njezina ljubav se osjeća – sounds wrong; se should not be placed after ljubav like this.

General guideline:

Clitics like se, je, mi, ti tend to appear very early in the clause, usually in second position after the first stressed word or phrase.
Content words (nouns, adjectives, main verbs) can move more freely to adjust emphasis and flow, but the core grammatical relations do not change.