  We present detailed analysis of an extreme ultraviolet (EUV) wave and its
interaction with active region (AR) loops observed by the Solar Dynamics
Observatory/Atmospheric Imaging Assembly and the Hinode EUV Imaging
Spectrometer (EIS). This wave was initiated from AR 11261 on 2011 August 4 and
propagated at velocities of 430--910 km\s. It was observed to traverse another
AR and cross over a filament channel on its path. The EUV wave perturbed
neighboring AR loops and excited a disturbance that propagated toward the
footpoints of these loops. EIS observations of AR loops revealed that at the
time of the wave transit, the original redshift increased by about 3 km\s,
while the original blueshift decreased slightly. After the wave transit, these
changes were reversed. When the EUV wave arrived at the boundary of a polar
coronal hole, two reflected waves were successively produced and part of them
propagated above the solar limb. The first reflected wave above the solar limb
encountered a large-scale loop system on its path, and a secondary wave rapidly
emerged 144 Mm ahead of it at a higher speed. These findings can be explained
in the framework of a fast-mode magnetosonic wave interpretation for EUV waves,
in which observed EUV waves are generated by expanding coronal mass ejections.
