Complex sentence: The CIA has been involved in the Democratic Republic of the Congo sporadically for several decades, most notably in relation to the CIA's considerations and plans to assassinate former Prime Minister Patrice Lumumba and accusations of CIA involvement in his eventual assassination.
Split into simpler sentences: The CIA has been involved in the Democratic Republic of the Congo sporadically for several decades. Most notably in relation to the CIA's considerations and plans to assassinate former Prime Minister Patrice Lumumba and accusations of CIA involvement in his eventual assassination.