Complex sentence: In effect, the area west of the railway line in Dunmurry, including Blacks Road and Areema will transfer to West Belfast, while the opposite side of the village and the village itself, which is part of the Seymour Hill ward will remain within Lagan Valley.
Split into simpler sentences: In effect, the area west of the railway line in Dunmurry, including Blacks Road and Areema will transfer to West Belfast. Whereas the opposite side of the village and the village itself, which is part of the Seymour Hill Ward will remain within Lagan Valley.