  The plasma oscillations of the two-dimensional electron-hole system in the
presence of a Rashba spin-orbit coupling are studied. Only the intra-Landau
level excitations are taken into account when the electrons and holes are
situated on their lowest Landau levels, the filling factor $v^{2}$ being less
than 1. The ground state of the two-dimensional electron-hole system is
supposed to be the electron-hole liquid. The dispersion relations for the
optical and acoustical plasmon modes were obtained. The acoustical plasmon
branch has a linear dispersion law in the range of small wave vectors and
monotonically increases with saturation at higher values of wave vectors. The
optical plasmon branch has a quadratic dependence in the range of long
wavelength and a monotonic increasing with saturation as in the case of
acoustical branch.
