We just learned about the Engine Block of a car.
One part of the engine block is the Cylinder.
The engine has a piston that goes up and down to make the car move, and the cylinder is the place that holds the piston.
Sometimes a car will 4, 6 or 8 cylinders depending on how many pistons there are.
![cylinder](https://upload.wikimedia.org/wikipedia/commons/0/0e/Cylinder_engine_%28PSF%29.png)
(from: wikipedia - cylinder (engine))
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