Um leið og sólin kemur aftur, opnum við gluggann eftir rigninguna.

Um leið og is a fixed expression that often means as soon as, when, or just as.

Literally, um leið has the idea of at the same moment / at once, and og introduces the following clause. So in a sentence like this, um leið og sólin kemur aftur means something like as soon as the sun comes back / comes out again.

It is a very common way to introduce a time clause.

This is because Icelandic usually follows a verb-second pattern in main clauses.

The first slot in the sentence is already taken by the whole time clause:

Um leið og sólin kemur aftur

After that, the finite verb of the main clause comes next:

opnum

And then the subject:

við

So the structure is:

[time clause] + [verb] + [subject] + [object]

That is why you get:

Um leið og sólin kemur aftur, opnum við gluggann ...

and not ... við opnum ... in this word order.

In Icelandic, the definite article is usually attached to the end of the noun instead of being a separate word.

So:

• sólin = the sun
• gluggann = the window
• rigninguna = the rain

This attached the changes form depending on the noun’s gender, number, and case, which is why it does not look the same in all three words.

Sól is the basic dictionary form, meaning sun.

Sólin means the sun. The ending -in is the suffixed definite article here.

It is also in the nominative case because sólin is the subject of kemur:

sólin kemur = the sun comes

So sólin tells you both:

• it is definite: the sun
• it is the subject of the clause

Kemur is the 3rd person singular present tense of að koma (to come).

It is 3rd person singular because the subject is sólin, which is singular:

• ég kem = I come
• þú kemur = you come
• hann/hún/það kemur = he/she/it comes

Since sólin is treated like hún (she, grammatically feminine), the verb form is kemur.

The dictionary form is gluggi = window.

Here it is the direct object of opnum (we open), so it has to be in the accusative case.

Because it is also definite (the window), the form becomes gluggann.

So:

• gluggi = a window / window
• glugginn = the window, nominative
• gluggann = the window, accusative

In this sentence, we open the window, so the accusative form is needed.

Here eftir means after, in a time sense.

In this kind of expression, eftir is followed here by the accusative, so rigning changes form:

• rigning = rain
• rigningu = rain, accusative
• rigninguna = the rain, accusative definite

So eftir rigninguna means after the rain.

The ending shows both:

• the case required here
• that it is definite: the rain

Not necessarily. Icelandic, like English, often uses the present tense in time clauses and for repeated or expected actions.

So this sentence can describe:

• something habitual: Whenever the sun comes back, we open the window after the rain
• something near-future: As soon as the sun comes back, we’ll open the window after the rain

English does something similar. We say:

• When the sun comes back, we open the window
• or When the sun comes back, we’ll open the window

We usually do not say when the sun will come back in that kind of clause, and Icelandic works similarly.

Aftur usually means again or back.

In sólin kemur aftur, it gives the idea that the sun returns or comes out again after the rain or clouds.

So it is not just the sun comes, but more specifically the sun comes back / returns / comes out again.

With weather, this kind of wording is very natural in Icelandic.

The comma separates the introductory subordinate clause from the main clause:

• Um leið og sólin kemur aftur = subordinate time clause
• opnum við gluggann eftir rigninguna = main clause

So the comma helps show the structure clearly. It is similar to English punctuation in sentences like:

When the sun comes back, we open the window.