Complex sentence: In 1993 he switched to bass guitar and continued his studies in the Helsinki Pop Jazz Conservatory (1994--2004) additionally he has taken lessons on piano, double bass, trumpet and male vocals.
Split into simpler sentences: In 1993 he switched to bass guitar and continued his studies in the Helsinki Pop Jazz Conservatory (1994--2004). Additionally he has taken lessons on piano, double bass, trumpet and male vocals.