Complex sentence: The east side has a long coastline along the South China Sea while the west borders Dongzhai Harbor, Haikou's Meilan District, Qionghai, and Ding'an County.
Split into simpler sentences: The east side has a long coastline along the South China Sea. The west borders Dongzhai Harbor, Haikou's Meilan District, Qionghai, and Ding'an County.