I am studying star-formation processes, Galactic structure, and interstellar chemistry by observing radio molecular lines and masers using radio telescopes, in particular radio interferometers (e.g. ALMA) and very long baseline interferometer (e.g. VERA). Current research interests are distance measurements of star-forming regions via VLBI astrometry of maser sources, measurements of 3D dynamical structures of molecular clouds and disk/jet systems of young stellar objects, search for interstellar molecules, observational studies of chemical compositions/processes and their evolution in molecular clouds, and new sciences with millimeter/submillimeter masers.