Complex sentence: He graduated top of his class in April 1905, was promoted to second lieutenant, and was sent to serve in the 13th Yerevan Grenadier Regiment, which was then stationed in Manglisi, Georgia.
Split into simpler sentences: He graduated top of his class in April 1905. Laidoner was promoted to second lieutenant and was sent to serve in the 13th Yerevan Grenadier Regiment, which was then stationed in Manglisi, Georgia.