Complex sentence: Under Diệm, the Special Forces were headed by Colonel Lé Quang Tung, who ad been trained by the Central Intelligence Agency (CIA) in the United States and commanded some 1,840 men under the direction of Nhu.
Split into simpler sentences: Under Diệm, the Special Forces were headed by Colonel Le Quang Tung. Tung had been trained by the Central Intelligence Agency in the United States and commanded some 1,840 men under the direction of Nhu.