Hún stendur við gluggann og horfir út.

Stendur is the 3rd person singular present tense of the verb standa, which means to stand.

So:

• að standa = to stand
• ég stend = I stand
• þú stendur = you stand
• hún stendur = she stands

In this sentence, Hún stendur means she is standing.

Icelandic normally uses an explicit subject, just like English often does.

• hún = she
• stendur = stands / is standing

So Hún stendur simply means She is standing.

In Icelandic, the verb changes depending on the person and number, but the subject pronoun is still very commonly included.

Here, við means by, at, or next to.

So:

• við gluggann = by the window / at the window

This is a very common preposition in Icelandic, but its meaning depends on context. In other sentences, við can also mean things like against, with, or toward, depending on usage.

In this sentence, the location meaning is the important one: she is standing by the window.

Gluggann is the form of gluggi used after the preposition við here.

The dictionary form is:

• gluggi = window

But Icelandic nouns change form depending on case and definiteness.

Here:

• gluggi = a window (nominative singular)
• gluggann = the window (accusative singular definite)

So við gluggann means by the window.

The -nn at the end is the definite article, roughly like English the, but in Icelandic it is attached to the noun.

Because við normally governs the accusative case.

That means the noun after við has to appear in an accusative form.

So:

• gluggi → basic dictionary form
• gluggann → accusative singular definite

This is something learners need to memorize with prepositions: many Icelandic prepositions require a particular case.

So even though English says by the window, Icelandic expresses it with við + accusative.

Og means and.

It joins the two verb phrases:

• Hún stendur við gluggann
• (hún) horfir út

In English, we also do this:

• She stands by the window and looks out.

The second hún is not repeated because it is understood from the first part.

Horfir is the 3rd person singular present tense of horfa, which means to look or to watch.

So:

• að horfa = to look / to watch
• hún horfir = she looks / she is looking

In this sentence, horfir works with út to give the sense looks out.

Út means out or outward.

In horfir út, it gives the sense of looking out, usually in the sense of looking outside, often through a window.

So:

• horfa = look
• horfa út = look out

This is very natural Icelandic. English also uses look out, so the structure is fairly easy to remember here.

It can suggest either, depending on context, but in this sentence it most naturally means looks out, with the idea that she is standing at the window and looking outside.

Because the sentence already mentions the window, the overall meaning is very likely:

• she is standing by the window
• she is looking out through it / looking outside

So the Icelandic sentence gives the same general picture as English She is standing by the window and looking out.

Because Icelandic, like English, does not need to repeat the subject when two verbs share the same subject and are joined by og.

So:

• Hún stendur við gluggann og horfir út.

literally works like:

• She stands by the window and looks out.

You could think of it as:

• Hún stendur við gluggann og hún horfir út.

But that would usually be unnecessary and less natural unless you wanted emphasis.

It can do either, depending on context.

The Icelandic present tense often covers both:

• She stands by the window and looks out
• She is standing by the window and looking out

Without more context, English may choose the progressive form, because it sounds more natural for a scene happening right now. But Icelandic commonly uses the simple present in places where English prefers is standing or is looking.

A rough learner-friendly approximation might be:

Hoon sten-dur vith GLUG-gan(n) ohk HORE-vir oot

A few useful notes:

• ú in út is like oo in food, but longer
• ð in við is often like the th in this
• gg in gluggann is pronounced distinctly, not like English silent letters
• the stress in Icelandic usually falls on the first syllable of the word:
  • HÚN
  • STENdur
  • VIÐ
  • GLUGgann
  • HORfir
  • ÚT

This is only a rough guide, but it can help you get started.

Yes. Depending on context, all of these can be reasonable:

• by the window
• at the window
• next to the window

By the window is probably the most natural general translation, but at the window is also perfectly possible in English. The Icelandic phrase mainly tells you her position relative to the window.