Learn Hardcore Icelandic: Staðirnir sem ég dreymi stundum um eru langt frá borginni. - The places that I sometimes dream about are far from the city.

Staðirnir – the places (main clause subject)
sem – that / which, introducing a relative clause that describes staðirnir
ég dreymi stundum um – I sometimes dream about

So the relative clause sem ég dreymi stundum um narrows down which places we’re talking about: not all places, only the ones the speaker sometimes dreams about.

Why is the preposition um at the end of the relative clause? Could it go somewhere else?

In sem ég dreymi stundum um, the preposition um (about) is stranded at the end, very much like in English:

English: the places that I dream about
Icelandic: staðirnir sem ég dreymi um

This is natural Icelandic when a preposition belongs with the relative pronoun sem but sem itself doesn’t carry a visible case ending.

You can move stundum (sometimes) around a bit, but um still tends to stay close to the verb or at the end of the clause:

sem ég stundum dreymi um
sem ég dreymi um stundum

All are understandable; the given version sem ég dreymi stundum um is perfectly normal and idiomatic. Putting um right after sem (sem um ég dreymi) would be wrong.

Why is it ég dreymi and not something like mig dreymir that I’ve also seen?

Icelandic has two common ways to talk about dreaming:

Personal, with a preposition (like English):
- Ég dreymi um þessa staði.
  = I dream about these places.
  Here ég is the subject, dreymi is a normal verb, and um introduces what you dream about.
Impersonal, with an object in accusative:
- Mig dreymir um þessa staði.
  Literally: It dreams me about these places → I dream about these places.

Both are used in modern Icelandic. Your sentence chooses the personal pattern:

sem ég dreymi stundum um
= that I sometimes dream about

So ég dreymi (um …) is like English I dream (about …); mig dreymir (um …) is more uniquely Icelandic and a bit more old‑fashioned/formal in some people’s usage, but still common.

How is dreyma conjugated here, and what tense is dreymi?

The verb is dreyma (to dream). In the present indicative, it conjugates:

ég dreymi – I dream
þú dreymir – you (sg.) dream
hann / hún / það dreymir – he / she / it dreams
við dreymum – we dream
þið dreymið – you (pl.) dream
þeir / þær / þau dreyma – they dream

So ég dreymi is 1st person singular present tense: I dream / I am dreaming (Icelandic doesn’t have a separate continuous form).

Technically dreymi can also be a subjunctive form, but in this straightforward statement it’s understood as present indicative.

What exactly does staðirnir mean, and why does it end in -nir?

The base noun is:

staður – place (masculine, singular, nominative)

The plural and definite forms are:

staðir – places (plural, nominative, indefinite)
staðirnir – the places (plural, nominative, definite)

So -nir is the definite plural nominative ending for many masculine nouns. It’s the subject of the sentence:

Staðirnir … eru langt frá borginni.
= The places … are far from the city.

Why is it eru langt and not eru langir to agree with staðirnir?

Here langt is functioning adverbially, meaning far, not as an adjective long describing the places themselves.

eru langt frá borginni = are far from the city

If you were describing the quality of the places (e.g. long/lengthy), you would use an agreeing adjective:

Staðirnir eru langir.
= The places are long. (pretty odd meaning for “places”)

But when talking about distance, Icelandic usually uses langt (neuter singular form used adverbially):

Það er langt héðan. – It is far from here.
Þeir búa langt í burtu. – They live far away.

So langt here is like the English adverb far, not an agreeing adjective.

Why is it frá borginni and not just frá borg? What does the ending -inni show?

The noun is borg – city (feminine).

The preposition frá (from) requires the dative case, and you also have the definite article:

borg – a city (nominative, indefinite)
borg – city (dative, indefinite; same form)
borgin – the city (nominative/accusative definite)
borginni – the city (dative definite)

So:

frá borg – from a city (unusual; you’d normally specify or make it definite)
frá borginni – from the city

In this sentence we’re talking about a specific city that both speaker and listener know, so the definite form borginni is used.

What does stundum mean, and is its position fixed in the sentence?

Stundum means sometimes.

In the clause sem ég dreymi stundum um, it’s placed between the verb and the preposition:

ég dreymi stundum um – I sometimes dream about

Adverbs like stundum are fairly flexible. You could also say:

sem ég stundum dreymi um
sem ég dreymi um stundum

All are understandable; the differences are subtle and mostly about rhythm and emphasis. The given word order ég dreymi stundum um is natural and neutral.

Could the sentence be written with the impersonal mig dreymir instead? How would that look?

Yes, you can also phrase it with mig dreymir. For example:

Staðirnir sem mig dreymir stundum um eru langt frá borginni.

This means essentially the same:

The places that I sometimes dream about are far from the city.

The difference:

sem ég dreymi stundum um – personal construction (I am the subject)
sem mig dreymir stundum um – impersonal construction (literally “that it sometimes dreams me about”)

Both are grammatical. Many speakers use both patterns; the personal ég dreymi um … feels slightly more similar to English and is often easier for learners.

What is the basic word order of the whole sentence, and how would it change if I asked a question instead of making a statement?

In the statement:

Staðirnir sem ég dreymi stundum um eru langt frá borginni.

The basic pattern is:

Subject: Staðirnir sem ég dreymi stundum um
– The places that I sometimes dream about
Verb: eru – are
Rest of the predicate: langt frá borginni – far from the city

So: [Subject] – [Verb] – [Complement].

If you turn it into a yes/no question, Icelandic normally puts the verb first:

Eru staðirnir sem ég dreymi stundum um langt frá borginni?
= Are the places that I sometimes dream about far from the city?

The relative clause sem ég dreymi stundum um stays attached to staðirnir in the same place.