Complex sentence: A large part of the PPU's work involved providing for the victims of war; the PPU's members sponsored a house where 64 Basque children, refugees from the Spanish Civil War, were cared for.
Split into simpler sentences: A large part of the PPU's work involved providing for the victims of war. Its members sponsored a house where 64 Basque children, refugees from the Spanish Civil War, were cared for.