Complex sentence: The Q-ship would pose as an easy target for the U-boat but in fact carry hidden armament; a typical Q-ship might resemble an old tramp steamer calmly sailing alone near an area where a U-boat was reported to be operating.
Split into simpler sentences: The Q-ship would pose as an easy target for the U-boat but in fact carry hidden armament. A typical Q-ship might resemble an old tramp steamer calmly sailing alone near an area where a U-boat was reported to be operating.