Complex sentence: He was detained and interrogated several months by the secret service but saved his live by telling everything he knew of his fellow Breton separatists the members of the Irish republican army and relations with different German secret services.
Split into simpler sentences: He was detained and interrogated for several months by the secret service. He saved his live by telling everything he knew of his fellow Breton separatists, the members of the Irish Republican Army and relations with different German secret services.