Complex sentence: The book was first conceived by Allende when she received news that her 100-year-old grandfather was dying, and she began to write him a letter that ultimately became the manuscript of "The House of the Spirits".
Split into simpler sentences: The book was first conceived by Allende when she received news that her 100-year-old grandfather was dying. She began to write him a letter that ultimately became the manuscript of "The House of the Spirits".