  The discovery of stationary "EIT waves" about 16 years ago posed a big
challenge to the then favorite fast-mode wave model for coronal "EIT waves". It
encouraged the proposing of various non-wave models, and played an important
role in approaching the recent converging viewpoint, {\it i.e.} there are two
types of EUV waves. However, it was recently discovered that a stationary wave
front can also be generated when a fast-mode wave passes through a magnetic
quasi-separatrix layer (QSL). In this paper, we perform a magnetohydrodynamic
(MHD) numerical simulation of the interaction between a fast-mode wave and a
magnetic QSL, and a stationary wave front is reproduced. The analysis of the
numerical results indicates that near the plasma beta $\sim 1$ layer in front
of the magnetic QSL, part of the fast-mode wave is converted to a slow-mode MHD
wave, which is then trapped inside the magnetic loops, forming a stationary
wave front. Our research implies that we have to be cautious in identifying the
nature of a wave since there may be mode conversion during the propagation of
the waves driven by solar eruptions.
