Complex sentence: A torpedo bulkhead is a type of armor common on the more heavily armored warships, especially battleships and battlecruisers, of the early 20th century, designed to keep the ship afloat even if the main belt armor were to be penetrated by a torpedo.
Split into simpler sentences: A torpedo bulkhead is a type of armor common on the more heavily armored warships, especially battleships and battlecruisers of the early 20th century. It is designed to keep the ship afloat even if the main belt armor were to be penetrated by a torpedo.