Th particle in solids, liquids and gases differ in their level of organization, their spacing and their motion.
In a solid, particles are close together and locked in position in an organized structure, usually a regular crystal lattice. The atoms or molecules that make up a solid have vibrational motion but not translational motion, which means that they vibrate but don't move around. Solids have a definite shape and a definite volume. An analogy for a solid is a classroom of students sitting at desks. They're in orderly rows and aren't changing position but there's still movement in place.
In a liquid, the particles move freely and slip and slide past each other, exhibiting both vibrational and translational motion. Molecules in a liquid are usually a little farther apart than in a solid. Liquids have a definite volume but take on the shape of their container.
The particles of a gas are very far apart compared to those of a solid or liquid and are moving around very rapidly, showing both vibrational and translational motion. Gases don't have definite shape or volume. Unlike solids and liquids, gases can be compressed and expanded.