Learn Hardcore Icelandic: Hún talar við sjálfa sig þegar hún einbeitir sér.

It’s a preposition. tala við means “to talk to.” Don’t confuse this with við as the pronoun “we” (which is nominative and functions very differently).

Why do we need both sjálfa and sig?

sig is the third‑person reflexive pronoun (object), meaning “herself/himself/themselves,” and it must be used to show the action reflects back on the subject.
sjálfa is the agreeing form of the adjective sjálfur “self,” added for emphasis/idiom. In the phrase tala við (sjálfan) sig, adding sjálfa/sjálfan/sjálft is very common and idiomatic.
So sjálfa sig ≈ “her own self.”

Why is it specifically sjálfa sig (and not sjálfan sig or sjálft sig)?

Because it agrees with the subject’s gender and case:

Subject is feminine singular (hún), and the preposition við takes the accusative.
Feminine accusative singular of sjálfur is sjálfa.
Thus: sjálfa sig.
If the subject were masculine: Hann talar við sjálfan sig.
If neuter (e.g., a child): Barnið talar við sjálft sig.

Could I drop sjálfa and just say Hún talar við sig?

Yes, it’s grammatically fine. However, with this verb the idiomatic, most common form is to include sjálf-, i.e., tala við sjálfan/sjálfa/sjálft sig. Omitting it is understood but sounds less set‑phrase‑like.

Why is it sig after við, but sér after einbeitir?

Icelandic case is governed by prepositions and verbs:

við takes the accusative, so you get sig (accusative reflexive).
einbeita sér is a reflexive verb that requires the dative, so you get sér (dative reflexive).

What’s the difference between sig and sér?

They’re the same reflexive pronoun in different cases:

Accusative: sig
Dative: sér Which one you use depends on the governing preposition/verb. Importantly, third‑person reflexive forms always refer back to the subject of the same clause.

Does sig/sér always refer back to the subject? What if I mean “she talks to another woman”?

Yes—third‑person reflexive sig/sér always refers to the subject of its clause. To refer to another female, use non‑reflexive forms:

“She talks to her (another woman)”: Hún talar við hana.
Reflexive “to herself”: Hún talar við sjálfa sig.

Why is the word order in the þegar clause “hún einbeitir sér” and not something like inversion?

In subordinate clauses introduced by a subordinator like þegar (“when”), Icelandic typically uses normal S–V–(O) order: hún einbeitir sér. Verb‑second (V2) behavior applies to main clauses, not to these þegar clauses.

Can I front the time clause? For example, start with Þegar?

Yes: Þegar hún einbeitir sér, talar hún við sjálfa sig.
When the þegar clause comes first, put a comma after it.

How do I say “concentrate on something” explicitly?

Use einbeita sér að + dative:

Hún einbeitir sér að verkefninu (“She concentrates on the project”).
In your sentence, einbeita sér is used without an object to mean “concentrate (in general).”

Is tala við always “talk to,” not “talk with”?

Yes, tala við e-n means “talk to someone.” If you want “talk with” in a mutual sense, Icelandic still commonly uses tala við, or sometimes tala saman (“talk together”) for reciprocity.

What are the relevant verb forms here?

tala (to talk), present 3sg: hún talar
einbeita sér (to concentrate), present 3sg: hún einbeitir sér
Note that einbeita is almost always used reflexively in this sense.

Can I use the “is …‑ing” idea with vera að?

Yes, for ongoing action: Hún talar við sjálfa sig þegar hún er að einbeita sér (“…when she is concentrating”). Both versions are natural; vera að + infinitive emphasizes the ongoing process.

Quick gender/case cheat for the “self” adjective with reflexives?

Singular forms most relevant here:

Masculine: nominative sjálfur, accusative sjálfan
Feminine: nominative sjálf, accusative sjálfa
Neuter: nominative/accusative sjálft
Combine with the appropriate reflexive case: sig (acc), sér (dat), depending on context.