Complex sentence: San Bernardino is a city located in the Riverside-San Bernardino metropolitan area (sometimes called the Inland Empire), and serves as the county seat of San Bernardino County, California, United States.
Split into simpler sentences: San Bernardino is a city located in the Riverside-San Bernardino metropolitan area (sometimes called the "Inland Empire"). It serves as the county seat of San Bernardino County, California, United States.