Complex sentence: The Italian Union of Rationalist Atheists and Agnostics (UAAR) are the one and only nationwide association of atheists and agnostics in Italy, and it is completely independent from political parties or lobbies of any kind.
Split into simpler sentences: The Italian Union of Rationalist Atheists and Agnostics (UAAR) is the only nationwide association of atheists and agnostics in Italy. It is completely independent from political parties or lobbies of any kind.