Ég ætla að skreppa í apótekið eftir vinnu.

Ætla að + infinitive is a very common Icelandic way to express intention or a near-future plan.

So Ég ætla að skreppa... means something like:

• I’m going to pop...
• I intend to pop...
• I’m planning to pop...

It is not just a plain present tense; it tells you what the speaker plans to do.

Here að is the infinitive marker, similar to English to in to go.

After ætla, Icelandic normally uses:

• ætla að gera eitthvað = intend to do something

So:

• ætla = intend / be going to
• að skreppa = to pop out / to make a quick trip

Skreppa usually means to make a short, quick trip somewhere. It often has a casual, everyday feeling.

In this sentence, it suggests something like:

• pop to the pharmacy
• run to the pharmacy
• nip to the pharmacy

It sounds lighter and quicker than just fara (go).

Compare:

• Ég ætla að fara í apótekið. = I’m going to go to the pharmacy.
• Ég ætla að skreppa í apótekið. = I’m going to pop to the pharmacy.

Because í can take different cases depending on meaning.

With movement into / to a place, í takes the accusative.
With being in a place, í takes the dative.

Here the speaker is going to the pharmacy, so we use the accusative:

• í apótekið = to / into the pharmacy

If you were talking about being inside it, you would use the dative:

• í apótekinu = in the pharmacy

Yes. Icelandic usually puts the definite article on the end of the noun.

• apótek = pharmacy
• apótekið = the pharmacy

That final -ið is the definite article here.

This is a very common Icelandic pattern with some prepositions.

For í:

• accusative often shows movement toward/into something
• dative often shows location inside something

So:

• Ég fer í apótekið. = I go to the pharmacy.
• Ég er í apótekinu. = I am in the pharmacy.

English uses different prepositions here, but Icelandic often keeps the same preposition and changes the case instead.

Eftir vinnu is a very natural way to say after work in a general, routine sense.

Like in English, we often do not strongly specify the work when we mean the general activity or workday.

So:

• eftir vinnu = after work

If you want to refer to a more specific piece of work or a specific work period, eftir vinnuna can also be possible, but eftir vinnu is the most natural everyday phrasing here.

Here vinnu is used after eftir, which in this time expression takes the dative.

So:

• eftir vinnu = after work

The noun is vinna (work, feminine), and its dative singular form here is vinnu.

A useful thing to know: for this noun, vinnu is also the form you see in some other cases, so the form itself is not unique to the dative. The preposition tells you how it is functioning here.

Yes. That is completely natural.

You can say:

• Eftir vinnu ætla ég að skreppa í apótekið.

This means the same thing, but gives after work a little more emphasis.

Notice the word order: in an Icelandic main clause, the finite verb usually stays in second position. So when Eftir vinnu comes first, ætla comes next:

• Eftir vinnu
  • ætla
    • ég ...

Yes, very natural. It sounds like normal everyday spoken Icelandic.

It is especially natural because of skreppa, which is a common conversational verb for a quick errand.

A speaker might say this when talking casually about plans for later in the day.

A rough English-friendly guide would be something like:

yeg EYEHT-la ath SKREHP-pa ee ah-POH-tek-ith EF-tir VIN-nu

A few helpful notes:

• æ in ætla sounds roughly like eye
• skreppa has a clear skrep- sound
• í is a long ee
• ð in að and apótekið is like the th in this

This is only an approximation, but it should help you get started.