Learn Hardcore Icelandic: Við viljum búa þar sem grasið er grænna. - We want to live where the grass is greener.

búa – live/reside: Ég bý í Reykjavík. – I live in Reykjavík.
lifa – be alive / live (a life): Hann lifði lengi. – He lived a long time.
eiga heima – literally “have home”, also “to live/reside”: Ég á heima í Reykjavík.

In this sentence, búa is the natural verb, because you’re talking about where you want to reside.

What does þar sem mean, and how is it different from hvar?

Þar sem here means where, introducing a relative clause:
þar sem grasið er grænna – where the grass is greener.

Breakdown:

þar – there
sem – that/which

So literally it’s like “(there) where/that the grass is greener”.

Difference from hvar:

hvar – “where?” (question word): Hvar býrðu? – Where do you live?
þar sem – “where (the place where…)” in statements:
Við viljum búa þar sem grasið er grænna. – We want to live where the grass is greener.

So you use þar sem to describe a place, not to ask about it.

Could you leave out þar and just say sem grasið er grænna?

No, not in this sentence. Sem by itself does not mean where.

þar sem = “(in the place) where …”
sem alone usually corresponds to that/which/who:
maðurinn sem ég sá – the man that I saw

To express “where the grass is greener”, you need the full þar sem.

Why is the main clause word order Við viljum búa? How does word order work here?

Icelandic has a verb‑second (V2) rule in main statements: the finite verb typically comes in the second position in the clause.

In this sentence:

Við – subject in first position
viljum – finite verb in second position
búa – infinitive verb (can come later)

So Við viljum búa is the expected neutral word order: subject – finite verb – other material.
If you put something else first for emphasis, the verb still tends to stay second, e.g.
Þar viljum við búa. – There we want to live.

Why is it grasið and not just gras?

Grasið means the grass; gras means grass (without “the”).

Icelandic usually marks definiteness with a suffix on the noun instead of a separate word:

gras – grass
grasið – the grass

In the English sentence “where the grass is greener”, the noun is definite, so Icelandic also uses the definite form grasið.

What does the ending ‑ið in grasið mean exactly?

The ending ‑ið is the definite article attached to a neuter singular noun in the nominative/accusative.

For gras (neuter):

gras – grass
grasið – the grass
grasi – (to) the grass (dative)
grass – of the grass (genitive)

So gras + ‑ið → grasið, “the grass” as the subject of the verb er (“is”).

What form is grænna, and why doesn’t it look like grænn or grænt?

Grænna is the comparative form of the adjective grænn (green), agreeing with the neuter noun grasið.

Positive degree:

grænn – green (masc)
græn – green (fem)
grænt – green (neut) → grasið er grænt – the grass is green

Comparative degree:

base comparative of grænn is grænni, but it declines
with a neuter singular subject like grasið, the predicative form is grænna:
grasið er grænna – the grass is greener

So the change to ‑nna is just part of the regular comparative inflection; it’s still “green(er)” and must match the gender/number of gras.

How would I say “greener than here / than there” in Icelandic?

You use en for than in comparisons:

grasið er grænna en hér – the grass is greener than here
grasið er grænna en þar – the grass is greener than there
grasið er grænna en heima – the grass is greener than (at) home

So the pattern is: [comparative adjective] + en + [thing compared to].

Is “the grass is greener” an idiom in Icelandic too, like in English?

Yes, very similar. Icelandic has the full proverb:

Grasið er alltaf grænna hinum megin girðingarinnar.
– The grass is always greener on the other side of the fence.

Your sentence Við viljum búa þar sem grasið er grænna can be understood literally, but in context it often carries the same idiomatic idea: people think life would be better somewhere else.

Could I say Okkur langar að búa þar sem grasið er grænna instead? What’s the difference from Við viljum búa…?

Yes, that’s grammatical and natural, but the structure and nuance are a bit different.

Við viljum búa… – We want to live…
– vilja
- nominative subject (við)
  – more about a conscious wish/decision
Okkur langar að búa… – We feel like living… / We long to live…
– langa is an impersonal verb: it takes an object-like pronoun in the accusative (mig, þig, hann… / okkur, ykkur, þá…)
– okkur is the accusative of við
– often a bit more about desire/longing or what you feel like doing

Both are common; in many contexts they’re close in meaning.

Why do we use við and not okkur in this sentence?

Because við is the nominative form used for the subject of the verb.

Forms of “we”:

við – we (nominative, subject)
okkur – us (accusative/dative, object or after some prepositions)
okkar – our/of us (genitive, possessive)

In Við viljum búa…, “we” is the subject, so Icelandic uses við.
You only use okkur when “us” is in an object role, e.g. Hann sér okkur – He sees us, or with langa: Okkur langar…

How are ð and þ pronounced in this sentence?

In this sentence:

Við – ð is like the English th in “this” (voiced). The vowel is like “vee-th”.
þar – þ is like the th in “thing” (voiceless). So þar sounds like “thar” (with that “thing”-type th).

So:

Við ≈ vith (with “this”-type th)
þar ≈ thar (with “thing”-type th)

Why is the word order grasið er grænna and not er grasið grænna?

Grasið er grænna is a statement, so Icelandic uses normal subject–verb–complement order in this subordinate clause:

grasið – subject
er – verb
grænna – predicate adjective

Er grasið grænna? would be a yes/no question: “Is the grass greener?” – in that case, verb–subject inversion is normal.

Inside the þar sem clause here, you’re not asking a question; you’re just describing a place, so you keep grasið er grænna.