- A ramp is a kind of object
- A block is a kind of object
- Therefore, a block and a ramp are kinds of objects

- A block and a ramp are kinds of objects
- Sliding is a kind of moving
- A block is sliding down a ramp
- Friction occurs when two object 's surfaces move against each other
- So, friction occurs between the block and the ramp

- Friction occurs between the block and the ramp
- Friction causes the speed of an object to decrease
- A block is a kind of object
- Therefore, friction causes the speed of the block to decrease

Therefore, friction causes the speed of the block to decrease
Question: A student sets a block at the top of a wooden ramp. The student pushes the block. As the block slides down the ramp, it slows down and then comes to a stop. What force causes the block to slow down?
Context: - Friction causes the speed of an object to decrease 
- A ramp is a kind of object 
- Sliding is a kind of moving 
- A block is sliding down a ramp 
- A block is a kind of object 
- Friction occurs when two object 's surfaces move against each other