  We study $N=2$ supersymmetric $SU(2)/U(1)$ and $SL(2,R)/U(1)$ gauged
Wess-Zumino-Witten models. It is shown that the vector gauged model is
transformed to the axial gauged model by a mirror transformation. Therefore the
vector gauged model and the axial gauged model are equivalent as $N=(2,2)$
superconformal field theories. In the $SL(2,R)/U(1)$ model, it is known that
axial-vector duality relates a background with a singularity to that without a
singularity. Implications of the equivalence of these two models to space-time
singularities are discussed.
