Complex sentence: Warlords usually incorporated their prisoners into their armies; at least 200,000 men who were serving in the army of Gen. Wu were prisoners he had incorporated into his own army.A survey of one warlord garrison in 1924 revealed that 90% of the soldiers were illiterate.
Split into simpler sentences: Warlords usually incorporated their prisoners into their armies; at least 200,000 men who were serving in the army of Gen. Wu were prisoners he had incorporated into his own army. Carrol & Graf, 2004 page 111 A survey of one warlord garrison in 1924 revealed that 90% of the soldiers were illiterate.