Complex sentence: This document exists in four forms--one in Czech, one in Latin, two in German; one of them is written on a large piece of paper, about 50 cm by 50 cm, much like a poster, but written on both sides.
Split into simpler sentences: This document exists in four forms--one in Czech, one in Latin, and two in German. One of them is written on a large piece of paper, about, much like a poster, but written on both sides.