Complex sentence: For many years Didier Francois has worked together with the Nyckelharpa builder Joos Janssens for the further evolution of the instrument, later on with the nyckelharpa and bow builder Jean Claude Condi (Mirecourt) Didier François helped with the realization of a study instrument for children.
Split into simpler sentences: For many years François worked with the Nyckelharpa builder Joos Janssens for the further evolution of the instrument. Later with the nyckelharpa and bow builder Jean Claude Condi (Mirecourt), he helped with the creation of a study instrument for children.