Here's why:

* Gas: In a gas, the atoms or molecules are very far apart and move freely and randomly. They have no fixed shape or volume.

* Liquid: In a liquid, the atoms or molecules are closer together than in a gas, but still able to move past each other. This gives liquids a fixed volume, but no fixed shape.

* Solid: In a solid, the atoms or molecules are tightly packed and have a fixed shape and volume.

Therefore, a nonsolid state of matter where atoms or molecules are free to move past each other is liquid.