Ég ætla í hárgreiðslustofu á morgun, því mig langar í stutta klippingu.

Here ætla means something like intend / plan / be going to.

So Ég ætla í hárgreiðslustofu is a natural way to say I’m going to a hair salon or I’m planning to go to a hair salon. It is not exactly the same as the English future marker in I’m going to..., but in many everyday sentences it feels very close.

In Icelandic, prepositions do not match English one-for-one.

í can mean:

• in for location
• into / to for movement toward a place

In this sentence, the idea is movement toward the salon, so English uses to, even though Icelandic uses í.

So:

• Ég er í hárgreiðslustofu = I am in a hair salon
• Ég ætla í hárgreiðslustofu = I’m going to a hair salon

Because after í, Icelandic normally does not use the nominative.

The dictionary form is hárgreiðslustofa. Here it changes form because of case.

With movement, í takes the accusative, so:

• nominative: hárgreiðslustofa
• accusative: hárgreiðslustofu

A useful thing to know: with this noun, the accusative and dative singular happen to look the same, so you do not see the movement/location contrast in the form itself. But the grammar is still there.

Yes. Icelandic loves compound nouns.

hárgreiðslustofa is built from:

• hár = hair
• greiðsla = combing, styling
• stofa = room, salon, parlor

So the whole word means hair salon / hairdresser’s salon.

This is very normal in Icelandic, even when the result looks long to an English speaker.

Because the sentence means a hair salon, not the hair salon.

In Icelandic, definiteness is often shown with an ending on the noun. Here the noun is indefinite:

• í hárgreiðslustofu = to a hair salon

If you meant a specific salon already known in the conversation, you could say:

• í hárgreiðslustofuna = to the hair salon

á morgun means tomorrow.

This is easy to confuse with:

• í morgun = this morning

So:

• á morgun = tomorrow
• í morgun = this morning

This is one of the most common little time-expression mix-ups for learners.

Here því means because.

It introduces the reason:

• Ég ætla í hárgreiðslustofu á morgun = main statement
• því mig langar í stutta klippingu = reason

So the whole structure is: ..., because ...

In other contexts, því can have other functions, but here it is just the conjunction because.

Because langa is used impersonally in Icelandic.

The person who feels the desire is put in the accusative, not the nominative:

• mig langar = I want / I feel like
• literally, very roughly: me longs for

So:

• mig langar = I want
• þig langar = you want
• hana langar = she wants

This is a very important Icelandic pattern.

Both can often be translated as I want, but they are not exactly the same.

• mig langar í ... = I feel like / I want ...
• ég vil ... = I want ... / I intend ... / I insist on ...

In many situations, mig langar í sounds more natural for a personal desire, especially for things, experiences, food, or something you feel like having.

So mig langar í stutta klippingu sounds very natural for I want a short haircut.

Because the usual pattern is langa í eitthvað = to want / feel like something.

So the í belongs with the verb pattern:

• mig langar í kaffi = I want coffee / I feel like coffee
• mig langar í frí = I want a vacation
• mig langar í stutta klippingu = I want a short haircut

This is something you mostly learn as a fixed expression.

Because both the adjective and the noun have to match the grammar of the phrase.

The noun is klipping = haircut.
Here it appears in the accusative singular:

• klippingu

The adjective stuttur = short must agree with it in gender, number, and case:

• feminine
• singular
• accusative

So:

• stutta klippingu = a short haircut

This agreement is a central feature of Icelandic grammar.

Because the sentence has two clauses, and the second one gives the reason.

Icelandic normally separates this kind of clause with a comma:

• main clause: Ég ætla í hárgreiðslustofu á morgun
• reason clause: því mig langar í stutta klippingu

So the comma is standard punctuation here.

Yes. That is also correct and natural.

• Ég ætla í hárgreiðslustofu á morgun = shorter, very natural
• Ég ætla að fara í hárgreiðslustofu á morgun = more explicit, literally I intend to go to a hair salon tomorrow

Both work. The shorter version is common in everyday speech.