Breakdown of Orkustigið er oft lágt á eftirmiðdaginn.
vera
to be
oft
often
á
onto / on / in (static location) / on (a day of the week)
lágur
low
Questions & Answers about Orkustigið er oft lágt á eftirmiðdaginn.
Why do we use á eftirmiðdaginn rather than í eftirmiðdaginn in this sentence?
Because the sentence describes a habitual, recurring situation, which is signaled here by the word oft (often). For habitual or future actions happening during a part of the day, Icelandic uses the preposition á with the accusative case. If you were talking about a specific afternoon happening right now or in the past, you would use í + accusative instead.
Why does the adjective lágt end in -t?
It is agreeing with the subject of the sentence, orkustigið (the energy level). Because orkustigið is a neuter noun, the adjective takes the neuter nominative form lágt rather than the masculine dictionary form lágur.
Why does eftirmiðdaginn have the definite article attached for a general statement?
In Icelandic, prepositional time phrases referring to parts of the day almost always require the definite article, even when making a general or habitual statement. Therefore, it is always á eftirmiðdaginn and never just á eftirmiðdag.
Could I use seinni partinn instead of á eftirmiðdaginn here?
Yes! While eftirmiðdagur is perfectly correct, in casual spoken Icelandic people frequently use the phrase seinni partinn (literally 'the later part') to mean the afternoon. If you swap it in, you would just say Orkustigið er oft lágt seinni partinn without needing an extra preposition.