  It is shown that the SU(1,1)-like and SU(2)-like two-photon coherent states
can be combined to form a O(3,2)-like two-photon states. Since the O(3,2) group
has many subgroups, there are also many new interesting new coherent and
squeezed two-photon states. Among them is the two-photon sheared state whose
symmetry property is like that for the two-dimensional Euclidean group. There
are now two-phonon coherent states which may exhibit symmetries not yet
observed for photons, including sheared states. Let us note that both SU(1,1)
and S(3,2) are isomorphic to the symplectic groups Sp(2) and Sp(4)
respectively, and that symplectic transformations consist of rotations and
squeeze transformations.
