Liquids and gases have the ability to flow. Liquids have a definite volume but no definite shape, while gases have neither a definite volume nor a definite shape. As a result, both liquids and gases can flow or move easily from one place to another. On the other hand, solids have a definite volume and a definite shape due to strong molecular forces of attraction among their particles. Hence, solids are rigid and do not possess the ability to flow.