  In this paper, we study real hypersurfaces in complex Grassmannians of rank
two. First, the nonexistence of mixed foliate real hypersurfaces is proven.
With this result, we show that for Hopf hypersurfaces in complex Grassmannians
of rank two, the Reeb principal curvature is constant along integral curves of
the Reeb vector field. As a result the classification of contact real
hypersurfaces is obtained. We also introduce the notion of $q$-umbilical real
hypersurfaces in complex Grassmannians of rank two and obtain a classification
of such real hypersurfaces.
