Kinetic Theory of Matter explains the properties of liquids, in that the more energy a particle has the freer it is to move about neighboring particles. That is the case of the liquid. Particles that make up liquids are still in close proximity to one another. They do have enough thermal energy that their movements are not restricted to just vibrating. Particles that make up liquids can "roll" around neighboring particles, yet they do not have enough energy to break completely free of attractive forces. It is because of this that liquids have a definite volume but no definite shape. Liquids take the shape of the container that they are in.