  We studied dipole excitations in $^{10}$Be based on an extended version of
the antisymmetrized molecular dynamics, which can describe 1p-1h excitations
and large amplitude cluster modes. Toroidal and compressive dipole operators
are found to be good proves to separate the low-energy and high-energy parts of
the isoscalar dipole excitations, respectively. Two low-energy $1^-$ states,
the toroidal dominant $1^-_1$ state at $E\sim 8$ MeV and the $E1$ dominant
$1^-_2$ state at $E\sim 16$ MeV, were obtained. By analysis of transition
current densities, the $1^-_1$ states is understood as a toroidal dipole mode
with exotic toroidal neutron flow caused by rotation of a deformed
$^6\textrm{He}$ cluster, whereas the $1^-_2$ state is regarded as a
neutron-skin oscillation mode, which are characterized by surface neutron flow
with inner isoscalar flow caused by the surface neutron oscillation against the
$2\alpha$ core.
