Questions & Answers about Ég myndi hafa varað þig við, en ég var ekki heima.
How is the past hypothetical formed in Ég myndi hafa varað?
It follows the exact structure for past conditionals: the past subjunctive of munu (myndi) plus the infinitive hafa plus the supine of the main verb (varað). This creates the meaning 'would have warned' for an action that never actually happened.
Why is við separated from varað and placed after the object þig?
The full verb is the phrasal verb vara við (to warn). In Icelandic, when a phrasal verb takes a direct pronoun object like þig, the pronoun is generally placed between the verb and the particle.
Is þig in the accusative case because of the preposition við?
No, in this sentence við acts as an adverbial particle, not a preposition governing the noun. The pronoun þig is in the accusative simply because it is the direct object of the verb vara.
As a quick refresher, why do we use heima here instead of heim?
You use heima to indicate a static location (being 'at home'), which fits perfectly with the verb vera. You would use heim if there were movement involved, such as going or walking home.