Complex sentence: These elements are reflected in his earliest compositions, from 1915; following a period of drift and inactivity, a positive and lasting influence on his work arose from his meeting in 1916 with the Dutch composer Bernard van Dieren.
Split into simpler sentences: These elements are reflected in his earliest compositions, from 1915. Following a period of drift and inactivity, a positive and lasting influence on his work arose from his meeting in 1916 with the Dutch composer Bernard van Dieren.