Original sentence: The US Navy's O class submarines were created out of the lessons learned from the United States L class submarine.The class originally operated in the anti submarine role off the USA's East Coast.The steamer scored six hits on O-4'''s conning tower and pressure hull before her identity was discovered
Edited sentence: Group 1.Group 2'''.The United States Navy's O class submarines were created out of the lessons learned from the United States L class submarine.The class originally operated in the anti-submarine role off the USA's East Coast.The steamer scored six hits on O-4s conning tower and pressure hull before her identity was discovered