Complex sentence: In 2000, Amy joined Sony Music after her contract with Pony Canyon was ended in 1999, her fourth album, "Bintang Hati" was released and this was her first album with Sony Music.
Split into simpler sentences: In 2000, Amy joined Sony Music after her contract with Pony Canyon ended in 1999. Her fourth album, "Bintang Hati" was released and this was her first album with Sony Music.