Complex sentence: The West of England Main Line is the from London Waterloo to Exeter St Davids, historically the main line continued to Plymouth via Okehampton and competed for the lucrative Atlantic Boat Train traffic.
Split into simpler sentences: The West of England Main Line is the British railway line from London Waterloo to Exeter St Davids. Historically, the main line continued to Plymouth via Okehampton and competed for the lucrative Atlantic Boat Train traffic.