Complex sentence: Between 1945 and 1963,71 lives were lost in three major accidents in the mines, and in the summer of 1963 a commission established by the Storting delivered its report finding several deficiencies in the management of the mine.
Split into simpler sentences: Between 1945 and 1963,71 lives were lost in three major accidents in the mines. In the summer of 1963 a commission established by the Storting delivered its report finding several deficiencies in the management of the mine.