Learn Icelandic: Flugþjónninn stendur við gluggasætið. - The flight attendant m is standing by the window seat.

For prepositions like í (in) and á (on), yes! But við is a special case. When við is used to mean "by," "at," or "next to" a physical space, it takes the accusative case, even when there is no movement at all. That is why the sentence uses the accusative form gluggasætið.

How is the compound word gluggasætið put together?

It combines gluggi (window) and sæti (seat). When building compound nouns, Icelandic often puts the first word in the genitive (possessive) case. The genitive of gluggi is glugga, which attaches directly to sætið (the seat) to create gluggasætið.

Why is the definite article -inn on the flight attendant, but only -ð on the seat?

The ending changes based on the noun's gender. The base word þjónn (attendant/waiter) is masculine, so it takes the standard masculine "the" ending -inn. Sæti is a neuter noun ending in a vowel, so it just adds -ð in both the nominative and accusative cases.

Why does the verb standa (to stand) become stendur here?