One day, a little girl named Lily was in her room. She saw her dad load a big bookcase. The bookcase was fragile, so her dad was very careful. Lily wanted to help her dad. She said, "Dad, can I help you?"
Her dad smiled and said, "Yes, Lily. But you have to be very gentle with this bookcase. It's fragile."
Lily was very happy to help. She picked up a small book and put it on the bookcase. Suddenly, the bookcase started to shake! Lily and her dad were surprised. They didn't know what was happening.
A tiny mouse came out from behind the bookcase. It was the mouse that made the bookcase shake! Lily and her dad laughed. The mouse was very fast and ran away. They finished loading the bookcase and Lily learned to be careful with fragile things.
