Learn Icelandic: Öll fjölskyldan kom í athöfnina. - The whole family came to the ceremony.

In Icelandic, the word allur (here in the feminine singular form öll) is typically used with singular nouns to mean "the whole" or "entire." So öll fjölskyldan naturally means "the whole family." The word heill (whole/complete) is usually reserved for physical objects being unbroken, rather than groups of people.

Why do we use í to mean "to" here, rather than til?

When going to an event, gathering, or activity (like a ceremony, a party, or a class), Icelandic typically uses í. You generally use til when going to a person, a country, or certain places, but you go "into" (í) an event.

Why is athöfnina in the accusative case here?

The preposition í takes the accusative case when it describes movement toward a destination. Because the family is coming to the ceremony, it triggers the accusative. If the sentence described them already being at the ceremony, there is no movement, so you would use the dative form í athöfninni.

How do we know öll is the correct form to match fjölskyldan?

Fjölskylda (family) is a feminine noun, and it is the subject of the sentence, so it is in the nominative case. The adjective allur must agree in gender, number, and case, which makes it öll (feminine, nominative, singular).