How did women participate in the military during world war 2?

In WWII, women were prohibited by law from serving in combat units, but that didn't prevent them from actually being in combat.

The Womens' Army Corps (WAC) enlisted women to serve in administrative roles; bookkeeping, typing, generating reports, and as Stateside radio operators.

Nurses were sometimes the most visible women for combat soldiers; upon being evacuated to hospitals in areas removed from the fighting, they did heroic work in treating the injured. Women weren't supposed to go into combat, but sometimes combat came to THEM; a few nurses were captured by the Japanese during the early months of the war, and suffered unspeakable atrocities. And some nurses were killed by Japanese air raids.

Women served as "ferry pilots", flying bombers and fighters from the US, to Labrador, to Greenland, to Iceland, and then to England. This freed up men to fly those fighters and bombers into combat in France and Germany.

Nowadays, while women are generally not assigned to combat infantry roles, they can and do fly fighters, bombers, and support aircraft. In fact, the first woman fighter pilot to engage in combat (flying A-10 "Warthog" tank killers) over Iraq went on to command a fighter squadron, and then retired from the Air Force. In the November 2014 elections, LT. COL Martha McSally was elected to the US House of Representatives from Arizona.