Complex sentence: The destruction of the Temple is still mourned annually as the Jewish fast Tisha B'Av, and the Arch of Titus, depicting and celebrating the sack of Jerusalem and the Temple, still stands in Rome.
Split into simpler sentences: The destruction of the Temple is still mourned annually as the Jewish fast Tisha B'Av. The Arch of Titus, depicting and celebrating the Roman sack of Jerusalem and the Temple, still stands in Rome.