The key property that liquids and gases have that solids do not is fluidity.

Here's a breakdown:

* Fluidity: This means the ability to flow and take the shape of their container.

* Liquids: Have a definite volume but take the shape of their container. Think of water in a glass or a bottle.

* Gases: Have no definite volume or shape and expand to fill their container. Think of air in a balloon or a room.

* Solids: Have a definite volume and shape. They resist changes in shape and volume. Think of a rock or a piece of metal.

Let me know if you'd like to explore other differences between the states of matter!