When Austria-Hungary declared war on Serbia, it led to a much bigger war, involving many countries. Soldiers were sent to fight, and millions lost their lives. Families were left without fathers, brothers, and sons. Cities and villages were bombed, making it very hard for people to find food and shelter. Many people lived in fear. The war changed the way people lived and affected the world for many years.

The invasion of Belgium and Luxembourg caused a lot of fear and suffering. People had to leave their homes to escape the fighting. Cities were destroyed, and many innocent people were hurt or killed. Life became unsafe and very difficult for everyone living in those countries.

The killing of Archduke Franz Ferdinand made a lot of countries angry at each other. Soon, a big war started, World War I. Millions of soldiers had to fight, and many people died. Families lost their loved ones, cities were destroyed, and people did not have enough food or safety. Life became very hard for many, and the war changed the world forever.

When the U.S. joined World War I, it changed people's lives in many ways. Soldiers went to fight overseas, and families were worried about them. People at home supported the war by working in factories, growing food, and helping with other needs. 

The Treaty of Versailles made life hard for many people, especially in Germany. The country had to pay huge fines, which caused a lot of poor people and job loss. People faced high taxes, and the economy struggled. Many were angry about the treaty, which created political problems and helped leaders like Adolf Hitler rise to power.

The Battle of the Somme caused a lot of pain for people. Many soldiers died or were hurt, and their families were left grieving. It made people realize how terrible war was, especially because so many lives were lost for little land gained