Complex sentence: The surface of the Ivanovo region is gently undulating, sometimes flat, low-lying plain, the altitude of which only the extreme south-east of the region, where the boundary slopes are suitable Moscow Upland, reaches 212 meters above sea level.
Split into simpler sentences: The surface of the Ivanovo region is a gently undulating, sometimes flat, low-lying plain. The altitude, in only the extreme southeast of the region where the boundary slopes are suitable Moscow Upland, reaches 212 meters above sea level.