Peysan mín er rauð.

Because Icelandic usually puts the definite article on the end of the noun.

• peysa = sweater
• peysan = the sweater

In this kind of phrase, Icelandic normally says peysan mín for my sweater, not just peysa mín in the most neutral everyday style.

That is a very common Icelandic pattern with possessives.

English says:

• my sweater

Icelandic very often says, more literally:

• the sweater my = peysan mín

So the possessive pronoun often comes after the noun, especially in ordinary neutral speech.

Because mín has to agree with peyson? Wait no—agree with peysan, which is a feminine singular noun in the nominative.

The basic nominative singular forms are:

• minn = masculine
• mín = feminine
• mitt = neuter

Since peysa is feminine, you use mín.

You usually learn a noun’s gender along with the word itself. In a dictionary, it would be marked as feminine.

A helpful clue is that many Icelandic nouns ending in -a are feminine, and peysa is one of them. Once you know it is feminine, that affects the forms around it, such as:

• mín instead of minn/mitt
• rauð instead of masculine or neuter adjective forms

Because adjectives in Icelandic agree with the noun they describe in gender, number, and case.

Here, peysan mín is:

• feminine
• singular
• nominative

So the adjective must match that, giving rauð.

Compare:

• rauður = masculine
• rauð = feminine
• rautt = neuter

Because this adjective is being used predicatively—that is, after the verb to be.

In Peysan mín er rauð, the structure is:

• The sweater is red

After er (is), Icelandic uses the adjective in the predicative form: rauð.

But when the adjective comes directly before a definite noun, you often get a different form:

• rauða peysan = the red sweater

So:

• Peysan mín er rauð = predicative adjective
• rauða peysan mín = adjective directly modifying the noun

Er is the 3rd person singular present form of the verb vera (to be).

So:

• ég er = I am
• þú ert = you are
• hann/hún/það er = he/she/it is

Since peysan mín is singular, the sentence uses er.

It is in the nominative case because it is the subject of the sentence.

That is why the other words match it:

• peysan = nominative singular definite form
• mín = feminine singular nominative
• rauð = feminine singular nominative

So the whole sentence is built around a feminine singular nominative subject.

You may hear that kind of order, but peysan mín er rauð is the more neutral, everyday way to say my sweater is red.

Putting the possessive before the noun can sound more marked, emphatic, literary, or contrastive depending on context.

So as a learner, the safest normal pattern is:

• peysan mín = my sweater

Because that is just how this common Icelandic structure works.

English does not say:

• the my sweater

But Icelandic normally does use the definite noun plus the possessive:

• peysan mín
• bíllinn minn = my car
• húsið mitt = my house

So even though it looks strange from an English perspective, it is a standard pattern.

It can do both, depending on how it is used.

In this sentence, mín means my because it goes with a noun:

• peysan mín = my sweater

But it can also mean mine when it stands on its own:

• Peysan er mín = The sweater is mine

So the same Icelandic form can match either my or mine in English, depending on the sentence.