Here are the answers to your questions about the song "Over There":
1. "Over There" refers to going to fight in Europe during World War I.
2. "Yanks" and "Yankees" refer to Americans.
3. "Huns" refers to Germans, which was a derogatory term used by Allied forces during WWI to describe German soldiers.
4. The purpose of the song was to rally support for the U.S. involvement in WWI and encourage men to enlist in the army.
5. Three reasons men should join the army according to the lyrics are: to help the cause/Allies over in Europe, it's their duty, and