Shales are a kind of rock that breaks into thin layers.
Shales are often used to make bricks and tiles.
Examples:
The shales are used to make the roof of the house.
We found some shiny shales near the river.
The shales are under the ground.
The shales look like they are made of many pieces of paper.
The shales are so thin, you can see through them.
The shales are like a puzzle made of rock.