Complex sentence: She tells Marlowe that she learned from the LAPD that the stolen necklace belongs to a Mrs. Lewin Lockridge Grayle, the young wife of a wealthy and influential Bay City resident, and offers to have her hire Marlowe to find the necklace.
Split into simpler sentences: She tells Marlowe that she learned from the LAPD that the stolen necklace belongs to a Mrs. Lewin Lockridge Grayle, the young wife of a wealthy and influential Bay City resident. Anne offers to have her hire Marlowe to find the necklace.