Complex sentence: In early August 1942, "Scharnhorst" conducted exercises in cooperation with several U-boats and collided with the U-boat "U- 523" which caused damage that necessitated dry-docking for repairs.
Split into simpler sentences: In early August 1942, "Scharnhorst" conducted exercises in cooperation with several U-boats. During the maneuvers, she collided with the U-boat "U- 523", which caused damage that necessitated dry-docking for repairs.