Complex sentence: During his service, Presley's life was affected in several ways, beginning with the death of his mother, Gladys Presley, who died of a heart attack brought on by acute hepatitis and cirrhosis of the liver.
Split into simpler sentences: During his service, Presley's life was affected in several ways. First, his mother, Gladys, died of a heart attack brought on by acute hepatitis and cirrhosis of the liver.