Complex sentence: Living so far away from Portland was dangerous: only one family lived in the town in 1725, an Indian raid in 1745 and the murder of Job Burnal in 1751 represented the risks colonists undertook to live in the area.
Split into simpler sentences: Living so far away from Portland was dangerous: only one family lived in the town in 1725. An Indian raid in 1745 and the murder of Job Burnal in 1751 represented the risks colonists undertook to live in the area.