Complex sentence: Basilicata is the most mountainous region in the south of Italy, with 47% of its area of 9,992 km 2 covered by mountains, whereas 45% is hilly and 8% is made up of plains.
Split into simpler sentences: Basilicata is the most mountainous region in the south of Italy, with 47% of its area of 9,992 km 2 covered by mountains. Of the remaining area, 45% is hilly, and 8% is made up of plains.