sentences:  In 931, he served under Dương Đình Nghệ (the administrator of Zhou Cho Giao Chỉ) and quickly rose through the military ranks and government administration; by 934, he was promoted to the post of military governor of Ái Châu.After Dương Đình Nghệ was assassinated in a military coup in 938 by a usurper named Kiều Công Tiễn, he took control of the military and was well received.That same year, Ngô Quyền's forces defeated the rebel Kiều Công Tiễn and had him executed.