Complex sentence: In 2002, Liz returns to Harmony in response to a telephone call from Diana and is told about her true identity as Sheridan, her engagement with Luis, and Antonio's terminal illness.
Split into simpler sentences: In 2002, Liz returns to Harmony in response to a telephone call from Diana. Diana tells Liz about her true identity as Sheridan, her engagement with Luis, and Antonio's terminal illness.