Complex sentence: Roncalli was elected pope on 28 October 1958 at the age of 76 after eleven ballots and no one could have been more surprised with the election than himself, who had come to Rome with a return train ticket to Venice.
Split into simpler sentences: Roncalli was elected pope on 28 October 1958 at the age of 76 after eleven ballots. No one could have been more surprised with the election than Roncalli himself, who had come to Rome with a return train ticket to Venice.