Complex sentence: In a recently discovered letter, Erickson confirmed her relationship with the two men and the rivalry between them, indicating that when she first discovered Hill was injured, he explained to her that Appelquist had shot him, apparently out of jealousy.
Split into simpler sentences: In a recently discovered letter, Erickson confirmed her relationship with the two men and the rivalry between them. The letter indicates that when she first discovered Hill was injured, he explained to her that Appelquist had shot him, apparently out of jealousy.