Complex sentence: The southwestern border of the plate is called the Itoigawa-Shizuoka Tectonic Line, and is a region of faulting that traverses the width of central Honshu, but it has not generated any large earthquakes in the last 950 years.
Split into simpler sentences: The southwestern border of the plate is called the Itoigawa-Shizuoka Tectonic Line. It is a region of faulting that traverses the width of central Honshu, but it has not generated any large earthquakes in the last 950 years.