It is not a liquid at room temperature. You have to heat peanut butter up to make it a liquid. When you or your mom makes jello, it is first a liquid. You have to put it in the refrigerator so that it becomes a solid. These are yummy forms of matter with properties of a liquid and a solid.
Gases Run in place very fast for a minute.
You need oxygen to live. That's why you can only hold your breath for a certain amount of time. You can't see oxygen. It is a gas. A gas is matter that has no shape or size of its own.