Cluster structures in $^{19}$Ne are studied by
the microscopic cluster model, the generalized two-center
cluster model (GTCM).
In the GTCMcalculation, the coupled-channels
problem of ($^3$He+$^{16}$O) + ($\alpha$+$^{15}$O)
is solved, and the adiabatic energy surfaces, which are
the series of the energy eigenvalues as a function
of the He--O distance, are investigated. In the
adiabatic energy curves, the several local minima
are generated in the spatial region of the small core
distance, where the neutron hole inside of the
He or O nucleus is strongly coupled to the residual
nuclei. The energy spectra, which are
constructed from the strong coupling states, nicely
reproduce the the low-lying energy levels in the
$^{19}$Ne nucleus.
The extended microscopic calculations of
($^3$He+$^{16}$O) + ($\alpha$+$^{15}$O) + ($^5$He+$^{14}$O)
are performed in order to see the coupling effect of
the 5$p$-2$h$ configuration, which corresponds to
the shell model limit of the $^5$He + $^{14}$O cluster
configuration. The extended calculation suggests that
the $^5$He + $^{14}$O configuration plays an important
role on the formation of the 3$\slash$2$^+$ resonance at
0.5 MeV with respect to the $\alpha$ threshold.