Complex sentence: Hwaaksan is a mountain in South Korea whose area extends over Gapyeong County, Gyeonggi-do and Hwacheon County, Gangwon-do.
Split into simpler sentences: Hwaaksan is a mountain in South Korea. Its area extends over Gapyeong County in Gyeonggi-do and Hwacheon County in Gangwon-do.