Barnið situr við borðið.

the child

Breakdown of Barnið situr við borðið.

• borðið: the table
• sitja: to sit
• við: with

Questions & Answers about Barnið situr við borðið.

Why is there no separate word for “the” in Barnið situr við borðið?

Icelandic usually doesn’t use a separate word for “the”.
Instead, the definite article is attached to the end of the noun as a suffix.

• barn = child
• barnið = the child
• borð = table
• borðið = the table

So Barnið situr við borðið literally has “the” built into barnið and borðið, instead of using a separate word.

Why is it barnið and not just barn at the start of the sentence?

Because the sentence is talking about a specific, identifiable child, not just any child.
In Icelandic:

• barn situr við borð ≈ a child sits at a table (non‑specific)
• barnið situr við borðið = the child sits at the table (specific)

Adding -ið makes barn definite: the child.
So barnið is the nominative definite form of barn.

What grammatical case is barnið, and why?

Barnið is in the nominative singular.