The hybridization of $S$ in $S{F}_4$ is;

 The electronic geometry is trigonal bipyramidal when five pairs of electrons surround the core metal atom. If all electron pairs are shared, the molecular geometry will also be trigonal bi-pyramidal. If one of the electron pairs is not shared, the molecular structure is known as a distorted tetrahedron, sometimes known as a seesaw. ${\mathrm{SF}}_4$ is an example of a molecule having trigonal bi-pyramidal electrical geometry and a distorted tetrahedron molecular form.