How does the particle theory of matter explain why a gas has more compressibility than a liquid?

Solids, liquids and gases are different because the atoms
(or particles) that make them up have different amounts of energy.  The amount of energy
determines how the atoms or particles behave.  In solids the particles do not have much
energy.  The particles in solids are tightly packed and locked in place, but still
vibrate.  In liquids the particles have more energy.  This allows the particles in
liquids to roll past each other, but they are still tightly packed.  In gases the
particles have a lot of energy.  This means that they are
not tightly packed and can move apart.  Gases can be compressed because the particles
can be forced closer together.  The particles in a liquid are already as close as they
can be.