Complex sentence: As a U.S. Marine, Deibert promptly completed boot camp at Hood River; also, he attended radio telegraph school, both of these completions were prior to his introductory tour with the 1st Marine Regiment, whose Division was located at Camp Pendleton (OR).
Split into simpler sentences: As a U.S. Marine, Deibert promptly completed boot camp at Hood River; also, he attended radio telegraph school. Both of these completions were prior to his introductory tour with the 1st Marine Regiment, whose Division was located at Camp Pendleton (OR).