In a diagram of the particles in a liquid, make sure that they are mostly touching but randomly arranged. If there are large spaces between the particles, you would be able to compress the liquid.

Figure 4: Schematic diagram of the distortions around particles in nematic liquid crystal. The black lines represent the axis of preferential orientation of the liquid-crystal molecules.

The four fundamental states of matter are solid, liquid, gas and plasma, but there others, such as Bose-Einstein condensates and time crystals, that are man-made.