Breakdown of Ég er nýbúinn að horfa á draugalega bíómynd.
vera
to be
ég
I
bíómyndin
the movie
að
to (infinitive marker)
Questions & Answers about Ég er nýbúinn að horfa á draugalega bíómynd.
How does the suffix -legur work to create the word draugalega in this sentence?
The root is the noun draugur (ghost). By attaching the productive suffix -legur—which functions a lot like "-y", "-ly", or "-like" in English—it transforms the noun into the adjective draugalegur (ghostly or spooky).
Why does the adjective end in -lega here instead of its dictionary form -legur?
Adjectives must agree with the noun they modify. Here, it describes bíómynd (movie), which is a feminine noun. Because the verb phrase horfa á triggers the accusative case, the masculine nominative draugalegur changes to the feminine accusative draugalega.
Would nýbúinn change if a woman were saying this sentence?
Yes, it would become nýbúin. The construction vera búinn að (to have finished / to have just done) uses the past participle búinn, which acts like an adjective and must agree in gender and number with the subject. The prefix ný- adds the meaning of "newly" or "just", but the gender agreement rule stays exactly the same.
The preposition á can take either the accusative or dative case. Why is draugalega bíómynd in the accusative here?
The phrasal verb horfa á (to watch or look at) always governs the accusative case for the object being watched. You don't need to worry about the usual "motion versus location" rules that the preposition á sometimes uses; with horfa, it strictly takes the accusative.