Complex sentence: South Plains is a vernacular term that refers to a region in northwest Texas consisting of the Texas portion of the geographical Llano Estacado and the western portion of the lower part of the Southwestern Tablelands ecological region.
Split into simpler sentences: South Plains is a vernacular term that refers to a region in northwest Texas. The region consists of a portion of the Texas side of the geographical Llano Estacado and the western portion of the lower part of the Southwestern Tablelands ecological region.