Complex sentence: The 67th TFS ended its first duty at Korat on April 26 but returned from Okinawa on August 16 for a second tour of temporary duty with the 6234th TFW, flying combat missions over North Vietnam.
Split into simpler sentences: The 67th TFS ended its duty at Korat on April 26. On August 16,1965, the 67th TFS began its second tour of temporary duty with the 6234th TFW, flying combat missions over North Vietnam.