Complex sentence: Edna visits Mr. Denby once more to negotiate saving her farm from foreclosure; she realizes she cannot make the next payment in full even if she sells all 30 acres of her cotton.
Split into simpler sentences: Edna visits Mr. Denby once more to negotiate payment terms and save her farm from foreclosure. She realizes she cannot make the next payment in full even if she sells all 30 acres of her cotton.