If you have had the opportunity to go to the beach, you have probably felt grainy sand between your toes while in the water. If you take a scoop of sandy water, place it in a bottle, and try to shake it, what do you suppose will happen? Rather than dissolving in the water, the sand will float around and eventually settle to the bottom. This interaction between sand and water perfectly explains what a suspension is.
Suspension is a type of heterogeneous mixture where solid particles do not dissolve in a liquid solution. No matter how hard you shake or stir, think of suspended particles as stubborn substances unwilling to dissolve in a solution.