Complex sentence: Factors such as wealth and high population densities in cities forced the ancient Romans to discover new architectural solutions of their ond arches, together with a sound knowledge of building materials, enabled them to achieve unprecedented successes in the construction of imposing structures for public use.
Split into simpler sentences: Factors such as wealth and high population densities in cities forced the ancient Romans to discover new architectural solutions of their own. The use of vaults and arches, together with a sound knowledge of building materials, enabled them to achieve unprecedented successes in the construction of imposing structures for public use.