1. What were the underlying causes of WWI?

Some of the causes of WWI were nationalism, which caused tensions between different countries, imperialism, because it caused competition for colonies, alliances because people were worried that they may be isolated from everyone else and when they joined they would have to help there allies fight.

2. What was the specific cause of WWI?

The main cause that WWI broke out was because of the assassination of the Archduke Ferdinand. Before WWI, there was a competition between the powers of Europe to have bigger armies and navies.

3. How did the soldiers react as they went off to war? Why?

Well, the soldiers reacted in a way like they felt that they had to go and defend their country. A lot of them were fired up to go and excited to be part of such a great nation's army. And others, with the help of persuasive arguments from their teachers and friends, went with only some doubts.