Complex sentence: No 238 Squadron was formed in August 1918 from Nos 347,348 and 349 Flights at the seaplane station at Cattewater, Plymouth, and flew anti-submarine patrols until the end of the war, being reduced to a cadre on 15 May 1919.
Split into simpler sentences: No 238 Squadron was formed in August 1918 from Nos 347,348 and 349 Flights at the seaplane station at Cattewater, Plymouth. The squadron flew anti-submarine patrols until the end of the war, being reduced to a cadre on 15 May 1919.