Complex sentence: The commandos undertook intensive training at Saitama Kanto and the raid was scheduled to take place on January 17,1945, but was cancelled after damage to the airfields at Iwo Jima.
Split into simpler sentences: The commandos undertook intensive training at Saitama Kanto and the raid was scheduled to take place on January 17,1945. Despite these preparations the operation was cancelled as a result of damage to the airfields at Iwo Jima.