Complex sentence: After the inquest, Edna Brent, one of Sheila's fellow secretaries, is confused by something said in evidence, and attempts to draw it to Hardcastle's attention; but he is too busy to speak to her.
Split into simpler sentences: After the inquest, Edna Brent, one of Sheila's fellow secretaries, is confused by something said in evidence. She attempts to draw it to Hardcastle's attention; but he is too busy to speak to her.