Complex sentence: For his 2011 exhibition of drawings at the Metropolitan Museum of Art, Serra reworked some of his earlier pieces on paper which had been damaged or destroyed, recreating them specifically for the show.
Split into simpler sentences: For his 2011 exhibition of drawings at the Metropolitan Museum of Art, Serra reworked some of his earlier pieces on paper. Some of the drawings that he reworked had been damaged or destroyed, and the artist recreated them specifically for the show.