Complex sentence: It is the second film in his "Ukraine Trilogy" (the first being "Zvenigora" (1928) and the third "Earth" (1930)) which are widely considered to be three of the greatest movies ever made.
Split into simpler sentences: It is the second film in his "Ukraine Trilogy", the first being "Zvenigora" (1928) and the third being "Earth" (1930). These are widely considered to be three of the greatest movies ever made.