Complex sentence: After a blazing row with Pete, James invited Kathy back to his place for a glass of wine, but when it became clear that James was attempting to seduce her, Kathy made her excuses and attempted to leave.
Split into simpler sentences: After a blazing row with Pete, James invited Kathy back to his place for a glass of wine. However, when it became clear that James was attempting to seduce her, Kathy made her excuses and attempted to leave.