Complex sentence: Today the Katy area includes the City of Katy but also the large sections of unincorporated Harris, Fort Bend and Waller counties and defined by the boundaries of the Katy Independent School District.
Split into simpler sentences: Today the Katy area includes the City of Katy, but also the large sections of unincorporated Harris, Fort Bend and Waller counties. It is defined by the boundaries of the Katy Independent School District.