Annotated Dialogue: At the Shop

Shopping for clothes is a perfect grammar workout, because the moment you point at something and say "I'll take that red sweater," Icelandic makes you stack three agreement decisions into one phrase: a demonstrative (þessa), a weak adjective (rauðu), and an accusative noun (peysu) — all feminine, all marked. Below is a realistic exchange in a shop, glossed line by line, then unpacked: the demonstrative + weak-adjective + accusative chain, asking the price, trying things on with máta, and quantities with af.

The dialogue

A customer (Viðskiptavinur) and a shop assistant (Afgreiðslumaður).

The standout phrase is þessa rauðu peysu — "that red sweater." Three words, three agreement decisions. Let's unpack it.

þessa rauðu peysu — demonstrative + weak adjective + accusative

When you point at a specific thing, you get a definite noun phrase, and Icelandic marks definiteness in a chain. Look at the parts of þessa rauðu peysu:

• þessa — "that/this," the demonstrative, in the accusative feminine;
• rauðu — "red," an adjective in its weak form (the -u ending);
• peysu — "sweater" (peysa, feminine), in the accusative.

Three things are happening at once, and they all hang together:

1. The demonstrative triggers the weak adjective. Icelandic adjectives have two whole sets of endings — strong (used when the noun is indefinite: rauð peysa = "a red sweater") and weak (used when the noun is already made definite by a demonstrative or article: þessi rauða peysa = "this red sweater"). After a demonstrative like þessi/þessa, the adjective must be weak. (Full paradigm: adjectives/weak-declension.)

2. The whole phrase is accusative, because it's the object of langa í / fá — what you want or take. So þessi → þessa, rauða → rauðu, peysa → peysu.

3. Everything is feminine, because peysa is feminine — and the demonstrative and adjective both agree with it.

Compare the indefinite version, which uses the strong adjective and no demonstrative:

Demonstratives: þessi, þetta and their cases

The demonstrative changes shape for gender and case, just like the adjective and noun it sits with. The base "this/that" forms are:

So "this red sweater" (feminine, object) is þessa rauðu peysu, but "this blue scarf" — trefill is masculine — would be þennan bláa trefil. The neuter þetta also doubles as the all-purpose "this/that" when you point without naming the thing: Hvað kostar þetta? ("How much is this?"). (More: determiners/demonstratives.)

Hvað kostar …? — asking the price, and the verb that takes a subject

To ask the price, the frame is Hvað kostar …? ("How much does … cost?"). A subtle point worth flagging: with kosta, the thing being priced is the subject (nominative), and the price is what follows — the opposite of how some learners expect it. So hún kostar sjö þúsund krónur = "it (the sweater) costs seven thousand krónur," with hún nominative.

Money agreement: króna is feminine, so its numerals are feminine — tvær krónur, þrjár krónur — though for round prices you'll often hear þúsund ("thousand," neuter): sjö þúsund krónur. (Prices and measures: numbers/money-and-measures.)

Má ég máta? — trying things on, sizes, and fit

Three shop verbs to lock in:

• máta — "to try on." Má ég máta hana? = "May I try it on?" (hana = the sweater, accusative object).
• passa — "to fit." Hún passar = "it fits." Add fullkomlega for "perfectly."
• vera í — "to wear / be in" (a size or garment): Ég er í miðstærð = "I'm a medium," literally "I'm in medium size."

To ask for a different size, Áttu þetta í stærra/minna? ("Do you have this in a bigger/smaller?") uses the comparative adjective. Stærð ("size") is feminine.

kíló af eplum — quantities with partitive af

For loose groceries by weight or amount, Icelandic uses af ("of") + the dative — the partitive af. So "a kilo of apples" is kíló af eplum: kíló (the measure) + af + eplum (the dative plural of epli, "apple"). The thing measured always goes in the dative after af.

Vocabulary and forms

Things English speakers get wrong here

Key Takeaways

• A demonstrative (þessi/þessa/þetta) makes the noun definite, so the adjective inside the phrase goes weak (the -u form): þessa rauðu peysu.
• Indefinite phrases ("a red sweater") use the strong adjective instead: rauða peysu. Same words, different endings.
• The whole object phrase is accusative after fá/langa í — demonstrative, adjective, and noun all agree.
• With kosta, the thing being priced is the subject (nominative): hún kostar ….
• Try things on with máta (+ accusative); ask for sizes with í stærra/minna; buy quantities with af
  • dative (kíló af eplum).