Við göngum frá kaupunum.

Við means we.

In ordinary Icelandic sentences, subject pronouns are usually stated, so Við göngum... is the normal full form. Even though the verb ending already shows person and number, Icelandic does not usually drop subject pronouns the way some other languages do.

Göngum is the 1st person plural present tense form of ganga.

So:

• ganga = the infinitive, to go / walk or part of a larger expression
• við göngum = we
  • present-tense verb form

Because those are different forms of the same verb:

• ganga = infinitive
• göngum = present tense, we
• gengum = past tense, we

This verb changes its stem vowel in different forms, so it is not fully regular. That is why the forms do not all look alike.

A few useful forms are:

• ég geng
• þú gengur
• við göngum
• við gengum

Not in a simple word-for-word way.

In this sentence, frá is part of the fixed expression ganga frá, which has the meaning you were shown. So it is better to learn ganga frá as a unit, rather than trying to read it as just walk + from.

Grammatically, though, frá still behaves like the preposition frá and is followed by the dative case.

Because frá takes the dative.

So after frá, the noun must appear in a dative form. That is why you get kaupunum, not kaupin.

A useful contrast is:

• kaupin = definite plural, nominative/accusative
• kaupunum = definite plural, dative

The dictionary form is kaup.

In this sentence, kaupunum is the definite dative plural form.

You can break it down like this:

• kaup = basic form
• kaupum = dative plural
• kaupunum = dative plural with the attached definite article

It shows two things at once:

• plural dative
• definite article (the)

So kaupunum is not just purchases/deals in general, but the purchases/deals in the dative plural.

This is very typical in Icelandic: instead of putting a separate word for the before the noun, Icelandic usually attaches the article to the end of the noun.

Because kaup is often used in plural or collective-looking forms in Icelandic, especially in set expressions.

This is one of those places where Icelandic may use a plural form where English would prefer something more singular or abstract. So it is best to learn the noun together with the expression, rather than expecting it to match English exactly.

This is the normal order for a basic Icelandic main clause:

• subject
• finite verb
• rest of the sentence

So:

• Við = subject
• göngum = finite verb
• frá kaupunum = rest

Also, Icelandic is a V2 language, which means the finite verb usually stays in the second position in a main clause. For example:

• Núna göngum við frá kaupunum.

Here Núna comes first, so göngum still stays second, and við moves after it.