Complex sentence: In the Postclassic period of Mesoamerican chronology Tenayuca was a settlement on the former shoreline of the western arm of Lake Texcoco, located approximately to the northwest of Tenochtitlan (the heart of present-day Mexico City).
Split into simpler sentences: In the Postclassic period of Mesoamerican chronology, Tenayuca was a settlement on the former shoreline of the western arm of Lake Texcoco. It was located approximately to the northwest of Tenochtitlan (the heart of present-day Mexico City).