Complex sentence: The Ramsays have been joined at the house by a number of friends and colleagues, one of them being Lily Briscoe, who begins the novel as a young, uncertain painter attempting a portrait of Mrs. Ramsay and James.
Split into simpler sentences: The Ramsays have been joined at the house by a number of friends and colleagues. One of them, Lily Briscoe, begins the novel as a young, uncertain painter attempting a portrait of Mrs. Ramsay and James.