Complex sentence: From 2012 to 2014, former member Somin and newest member Chaekyung was a member of DSP Media girl group Puretty with releasing Japanese single "Cheki ☆ Love" in 2012 and disbanded in 2014 with plans to reform into other groups.
Split into simpler sentences: From 2012 to 2014, former member Somin was a member of the now-defunct girl group Puretty. The group debuted in Japan with the song "Cheki ☆ Love" and disbanded in 2014 with plans to reform into other groups.