- 2013/04 - 現在 Professor, Faculty of Business and Commerce, Keio University
- 2007/04 - 現在 Associate Professor, Faculty of Business and Commerce, Keio University
- 2005/04 - 現在 慶應義塾大学言語文化研究所兼担所員
- 2005/04 - 現在 Associate Professor, Faculty of Business and Commerce, Keio University
- 2010/04 - 2012/03 Visiting Scholar, Department of Linguistics and Philosophy, Massachusetts Institute of Technology/ Department of Linguistics, University of Massachusetts, Amherst.
- 2004/04 - 2005/03 Part-time lecturer, University of Electro-Communications
- 2004/04 - 2005/03 Part-time lecturer, Aoyama Gakuin University
- 2000/03 - 2004/03 Associate Professor, Kyushu Institute of Technology
- 2001/08 - 2001/08 Part-time lecturer, The University of Kitakyushu
- 1999/04 - 2000/02 Assistant Professor, Kyushu Institute of Technology
- 1997/01 - 1998/05 Teaching Assistant, Department of Linguistics, University of Maryland at College Part
- 1995/08 - 1996/12 Research Assistant, Department of Linguistics, University of Maryland at College Park
- 1994/01 - 1995/12 Part-time lecturer、Department of Japanese, The US-Japan Culture Association
- 1994/01 - 1995/06 Teaching Assistant, Department of Japanese, Georgetown University
- 1987/04 - 1991/03 English Teacher, Shimura The 4th Junior High School