Conversation so far:
What was Ira Hayes' role in the World War II?
Hayes enlisted in the Marine Corps Reserve on August 26, 1942.
How long was Ira Hayes on the reserve?
In October 1942, Ira Hayes volunteered for Marine paratrooper training.
Did Ira Hayes' paratrooper training help him in World War II?
Ira Hayes' fought against the Japanese with his unit, Company K, 3rd Parachute Battalion, 1st Marine Parachute Regiment of the I Marine Amphibious Corps, during the Bougainville Campaign.
What happened after Ira Hayes graduated paratrooper training school?
Hayes graduated from the Parachute Training School and received his silver jump wings. On December 1, he was promoted to private first class.

Question: What did he do after he was Private First class?
Self-contained rewrite: What did Ira Hayes do after he was Private First class?