Complex sentence: New York State Route 18 is an east-west state route in western New York, running parallel to the south shore of Lake Ontario for most of its length between Niagara County and Monroe County.
Split into simpler sentences: New York State Route 18 is an east--west state highway in western New York, United States. It runs parallel to the south shore of Lake Ontario for most of its length between Niagara County and Monroe County.