Learn Icelandic: Ert þú hræddur við ókunnugt fólk? - Are you afraid of unfamiliar people?

You would answer Já, ég er það (Yes, I am it). Although this lesson covers gera það to replace active verbs, hræddur is an adjective describing a state, so we use the verb vera (to be) rather than gera (to do). In Icelandic, you cannot leave the verb hanging like in English ('Yes, I am'); you must replace the missing predicate with the pronoun það.

Why do we use the preposition við here instead of af for 'of'?

Adjectives of emotion or reaction often pair with specific prepositions that do not map directly to English. Being 'afraid of' something is always expressed as hræddur við. The preposition við governs the accusative case here, which is why ókunnugt fólk is in the accusative.

Would the word hræddur change if I were asking a woman this question?

Yes, it would. Hræddur is the masculine nominative singular form. If you are asking a woman, it must agree with her grammatical gender and become hrædd. For a non-binary person, you would use the neuter form hrætt.

Why is the adjective ókunnugt singular when fólk refers to multiple people?