The significant structure theory of liquids is tested by evaluating the radial distribution function. The calculations are based on face-centered cubic quasi-lattice structure, and the fluctuation in volume is used to describe the thermal displacements of molecules. It is shown that the local structure of liquids has inhomogeneous distributions. The correlation at long ranges becomes negligible because of the fluidized vacancies in our model. The calculations are performed for liquid argon, and the results are in good agreement with experiments.