Complex sentence: The trio of Silent Circle first performed in 1976 and met with considerable success but soon parted ways.Untill in early 80s they met again and decided to form some solidified group.Hence, that marked the beginning of "Silent Circle".
Split into simpler sentences: The trio of Silent Circle first performed in 1976 and met with considerable success but soon parted ways. Until in early 80s they met again and decided to form some solidified group.Hence, that marked the beginning of "Silent Circle".