Complex sentence: He studied military engineering at the Academy of Military Engineering in Guadalajara, Spain from September 1885 to July 1900 and graduated with a degree in civil engineering with a lieutenant's commission in the Spanish Army.
Split into simpler sentences: He studied military engineering at the Academy of Military Engineering in Guadalajara, Spain from September 1885 to July 1900. He graduated with a degree in civil engineering and was commissioned a lieutenant in the Spanish Army.