Complex sentence: In Jerusalem, he built the Schocken Library, also designed by Erich Mendelsohn, was a board member of the Hebrew University of Jerusalem, and bought the newspaper "Haaretz", 60% of which is still owned by his family.
Split into simpler sentences: In Jerusalem, he built the Schocken Library, also designed by Erich Mendelsohn. He was a board member of the Hebrew University of Jerusalem and bought the newspaper "Haaretz", which is still owned by his family.