Learn Hardcore Icelandic: Stelpan er líka feimin þegar hún kynnir sig í partíinu. - The girl is also shy when she introduces herself at the party.

Here stelpan is the subject of the sentence and we’re talking about a specific girl, so the definite form is used in the nominative singular feminine.

What does líka mean here, and why is it placed after er?

Líka means "also / too / as well".

Word order:

Stelpan er líka feimin
Literally: The-girl is also shy.

In Icelandic main clauses, the finite verb (here er) normally comes in second position, and many adverbs like líka usually come right after the verb:

Hún er líka þreytt. – She is also tired.
Við förum líka. – We’re going too.

Other placements (e.g. Stelpan líka er feimin) sound odd or marked. So er líka is the natural, neutral order.

Why is the adjective feimin and not feiminn?

The dictionary form is feiminn (masculine nominative singular: shy), but adjectives in Icelandic must agree with the noun in:

Gender
Number
Case

Here the noun is stelpan:

Gender: feminine
Number: singular
Case: nominative (subject)

So feiminn changes to the feminine nominative singular form:

Masculine: feiminn
Feminine: feimin
Neuter: feimið

Because stelpan is feminine, we get:

Stelpan er feimin. – The girl is shy.

What does þegar do in this sentence?

Þegar is a conjunction meaning "when" (often like "whenever" in the present tense).

It introduces a subordinate clause:

þegar hún kynnir sig í partíinu
= when she introduces herself at the party

So the sentence has two parts:

Stelpan er líka feimin – main clause
þegar hún kynnir sig í partíinu – when-clause, explaining in what situation she is (also) shy.

In Icelandic, word order changes in subordinate clauses: you no longer need the verb in second position; you get the more “normal” subject–verb order:

þegar hún kynnir sig (subject hún, then verb kynnir)

Why do we repeat hún? Could we just say þegar kynnir sig?

In Icelandic you normally must have an explicit subject in finite clauses. Icelandic is not a “subject-dropping” language like Spanish or Italian.

So:

þegar hún kynnir sig
is correct (subject hún = she)

But:

þegar kynnir sig
is ungrammatical, because there is no subject.

Even if you just mentioned stelpan right before, you still need to say hún in the subordinate clause.

What exactly does kynnir sig mean? Why do we use sig here?

The verb is að kynna (einhvern) = to introduce (someone).

að kynna sig = to introduce oneself

So:

hún kynnir sig = she introduces herself

We use sig because it is the reflexive pronoun in the accusative case, referring back to the subject of the clause (hún).

Reflexive pronoun (singular & plural, all genders):

Accusative: sig
Dative: sér
Genitive: sín

The verb kynna einhvern takes an accusative object, so we need sig (accusative), not sér or sín.

What is the difference between að kynna sig and að kynnast?

They look similar but mean different things:

að kynna sig
– literally: to introduce oneself
– structure: kynna + accusative object
- Hún kynnir sig. – She introduces herself.
að kynnast (e-m)
– to get to know (someone)
– structure: kynnast + dative object
- Hún kynnist nýjum vinum. – She gets to know new friends.

So, in your sentence, kynnir sig is specifically about self‑introduction, not about getting to know other people better.

Why is it í partíinu and not just í partíi?

Two main points: definiteness and case.

Definiteness
- partí = a party (indefinite)
- partíið / partíinu = the party (definite, different cases)
Here the context is a specific party, so we use a definite form: the party.
Case after the preposition í
The preposition í (in / at) can take accusative (movement into) or dative (location in/at).
- Ég fer í partíið. – I’m going into the party. (accusative)
- Ég er í partíinu. – I’m at/in the party. (dative)
In your sentence, she is in/at the party (no movement), so í takes the dative.
The noun partí (neuter) in definite dative singular becomes:
- partí → partíinu

Hence: í partíinu = at the party.

Why is the ending -inu on partíinu?

Because partí is a neuter noun, and we need:

singular
dative
definite

The typical neuter definite endings:

Nominative: -ið (e.g. partíið – the party as subject)
Accusative: -ið
Dative: -inu (e.g. í partíinu – in/at the party)
Genitive: -sins (e.g. partísins – of the party)

With the preposition í meaning location, we use dative, so we get partíinu.

Could we say á partíinu instead of í partíinu?

You may see both í partíi/partíinu and á partíi/partíinu in real usage.

General tendencies:

í partíinu – literally in the party; quite common and natural for being at a party.
á partíinu – literally on/at the party; also used, especially with á meaning “at (an event)” in many contexts.

Both can be acceptable, but í partíinu is very natural and fits the idea of being in that social situation/place.

Importantly, the case stays dative either way (í/á + dative for location):

í partíinu
á partíinu

Why is the verb tense present (er, kynnir) even though in English we might say “when she introduces herself”?

In Icelandic, the present tense is often used for general, habitual situations, just like the English simple present:

Stelpan er líka feimin þegar hún kynnir sig í partíinu.
= She is (in general) also shy when she introduces herself at (a) party.

The idea is not one single event in the past, but a repeated or typical situation. English also uses the present tense for that:

She is also shy when she introduces herself at parties.

If you wanted a specific past event in Icelandic, you would change both verbs to past:

Stelpan var líka feimin þegar hún kynnti sig í partíinu.
– The girl was also shy when she introduced herself at the party.