Complex sentence: Orogeny (Greek for "mountain generating") refers to natural mountain building, and may be studied as (a) a tectonic structural event, (b) as a geographical event, and (c) a chronological event.
Split into simpler sentences: Orogeny (Greek for "mountain generating") refers to natural mountain building. An orogenic event may be studied as (a) a tectonic structural event, (b) as a geographical event, and (c) a chronological event.