Gestgjafinn býður öllum kaffi, te, vatn og eplasafa, og við skálum þegar afmælisbarnið kemur.

The host offers everyone coffee, tea, water, and apple juice, and we make a toast when the birthday person arrives.

Breakdown of Gestgjafinn býður öllum kaffi, te, vatn og eplasafa, og við skálum þegar afmælisbarnið kemur.

• við: we
• þegar: when
• og: and
• kaffið: the coffee

Questions & Answers about Gestgjafinn býður öllum kaffi, te, vatn og eplasafa, og við skálum þegar afmælisbarnið kemur.

Why does gestgjafinn end in -inn? Is that “the”?

Yes. -inn is the suffixed definite article.

• gestgjafi = a host
• gestgjafinn = the host
  In Icelandic, the is usually attached to the noun (and agrees with gender/number/case).

How do I know the gender of gestgjafi and why does it matter here?

Gestgjafi is masculine. Gender matters because it affects:

• the definite article ending (-inn for masculine nominative singular),
• adjective forms (not used here),
• and some pronouns/determiners (like öllum agreeing with a plural noun phrase).

Why is it býður and not bjóða?

Býður is the 3rd person singular present form of bjóða (to offer / to invite).
The subject is gestgjafinn (the host), which is singular, so the verb is singular:

• ég býð, þú býður, hann/hún/það býður, við bjóðum, þið bjóðið, þeir/þær/þau bjóða

What case is öllum and why is it that form?