Learn Hardcore Icelandic: Hundurinn er sterkur.

Icelandic marks definiteness by adding a suffix to the noun. The base noun hundur (“dog”) takes the definite suffix -inn, giving hundurinn (“the dog”).

What grammatical case, number, and gender is hundurinn, and why?

hundurinn is masculine singular nominative. It’s the subject of the sentence, so it appears in the nominative case. hundur is a masculine noun, and here it’s singular.

What is er, and how does it function in this sentence?

er is the 3rd person singular present tense of vera (“to be”). It acts as the copula, linking the subject (hundurinn) to the predicate adjective (sterkur).

Why is sterkur not inflected with -inn like hundurinn?

Predicative adjectives (those following a copula) use the strong declension and never take a definite suffix. Here sterkur is the strong nominative singular masculine form, matching hundurinn.

How would you say a strong dog in Icelandic?

You use the indefinite noun and adjective before it: Sterkur hundur. Both words are in the strong nominative singular masculine.

How do you form a yes/no question from Hundurinn er sterkur?

Invert the verb and subject: Er hundurinn sterkur? (“Is the dog strong?”)

Can you replace hundurinn with a pronoun, and if so, which one?

Yes. You can say Hann er sterkur, using hann (“he”) for a masculine singular noun.

How do you negate the sentence?

Add ekki (“not”) after the verb: Hundurinn er ekki sterkur.