  Inclusive electron scattering off few-nucleon systems is investigated at
$x>1$ and high momentum transfer, including the contributions from
quasi-elastic and deep inelastic scattering processes. It is shown that at
$x>1$ the inclusive cross section is dominated by the process of virtual photon
absorption on a pair of correlated nucleons both in case of quasi-elastic and
deep inelastic scattering events. The sensitivity of the nuclear response to
the effects arising from the possible presence of multiquark cluster
configurations at short internucleon separations as well as from possible
medium-dependent modifications of the nucleon structure function, is
illustrated.
